spin 
The sharp streams (if milk spun and foamed into the 
pail below. It. T. Cooke, Somebody's Neighbors, p. B4. 
5. To no or move rapidly; go fast: as, to xpilt 
along the road. [Colloq.] 
While it [money] lasts, make it spin. 
1C. Collins, Hide and Seek, ii. 4. 
The locomotive spins along no less merrily because ten 
carloads of rascals may be profiting by its speed. 
S. Lanier, The English Novel, p. 3. 
6. To use a spinner or spinning-spoon ; troll: 
as, to spin for trout. 7. To be made to re- 
volve, as a minnow on the trolling-spoou. The 
minnow is fastened on a gang of small hooks that are 
thrust into its back and sides to so bend it that it may 
turn round and round when dragged through the water. 
Spinning dervish. See dervish. 
spin (spin), n. [< spin, r.] 1 . A rapid revolv- 
ing or whirling motion, as that of a top on its 
axis ; a rapid twirl : as, to give a coin a spin. 
She found Nicholas busily engaged in making a penny 
spin on the dresser, for the amusement of three little 
children. . . . He, as well as they, was smiling at a good 
long spin. Mrs. Oaskell, North and South, \ \ \ i \. 
2. A continued rapid motion or action of any 
kind ; a spirited dash or run ; a single effort of 
highspeed, as in running a race; a spurt. [Col- 
loq.] 3. In math., a rotation-velocity consid- 
ered as represented by a line, the axis of rota- 
tion, and a length marked upon that line pro- 
portional to the number of turns per unit of 
time. W. K. Clifford. 
spina (spl'nii), n.; pi. sjrinse (-ne). [< L. spina, a 
thorn, prickle, the backbone : see spine."] 1. In 
zool.&n&anat. : (a) A spine, in any sense. (6) The 
spine, or spinal column; the backbone: more 
fully called spina dorsalis or spina dorsi, also 
columna spinalis. 2. [cap.] [NL.] In ornith., 
a genus of fringilline birds, the type of which is 
S. lesbia of southern Europe. Kaup, 1829. Also 
called Buscarla. See Spinus. 3. In Bom. an- 
tiq., a barrier dividing the hippodrome longi- 
tudinally, about which the racers turned. 4. 
One of the quills of a spinet or similar instru- 
ment Erector spina, multifldus spinae, rotatores 
spinse. See erector, muttifldus, rotator. Spina angu- 
laris. See spine of the sphenoid, under spine. Spina 
bifida, a congenital gap in the posterior wall of the spi- 
nal canal, through which protrudes a sac, formed in hy- 
drorachis externa of meninges, and in hydrorachis in- 
terna of these with a nervous lining. This forms a tumor 
in the middle line of the back. Spina dorsalis, spina 
dorsi, the vertebral column. Spina frontalis. See 
nasal spine (a), under nasal. Spina helicis, the spinous 
process of the helix of the ear. Spina mentalis, one of 
the mental or genial tubercles. See mental'^, genial'^. 
spinaceous (spi-na'shius), a. [< Spinacia + 
-ous (accom. to -aceous).~] Of, pertaining to, or 
of the nature of spinach, or the class of plants 
to which it belongs. 
spinach, spinage (spin'aj), n. [() According 
to the present pron., prop, spelled spinage (early 
mod. E. also spynnage), this being an altered 
form of spinach (early mod. E. spinachc); = 
MD. spinagie, spinazi, D. spinazie = LG. spina- 
sie,( OF. spinache, espinache, espiuage, espiiiace, 
espitioce, espinoclie, espinoichc, etc., = Sp. espi- 
naca = Cat. espinac = It. spinace, also spinacchia, 
< ML. spinacia, spinacium, also spinacius, spi- 
nachia, spinachium, spinathia, etc., after Rom. 
(NL. spinacia), spinach ; cf. (6) Pr. cspinar, OF. 
espinars, espinard, espinar, F. epinard, < ML. 
"spinariiis, *spinarium, spinach; (c) G. Dan. 
spinat = Sw. spenat, spinat, < ML. "spinatum, 
spinach; (d) Pg. cspinafre, spinach (cf. L. spi- 
nifer, spine-bearing) ; so called with ref . to the 
prickly fruit ; variously formed, with some eon- 
fusions, < L. spina, a thorn: see spine.'] 1. A 
cheuopodiaceous garden vegetable of the genus 
Spiitacia, producing thick succulent leaves, 
which, when boiled and seasoned, form a pleas- 
ant and wholesome, though not highly flavored 
dish. There is commonly said to be but a single species, 
S. oleracea ; but S. glabra, usually regarded as a variety, 
is now recognized as distinct, while there are two other 
wild species. The leaves of S. oleracea are sagittate, un- 
divided, and prickly ; those of S. glabra are larger, round- 
ed at the base, and smooth. These are respectively the 
prickly-leaved andround-leaved spinach. There are several 
cultivated varieties of each, one of which, with wrinkled 
leaves like a Savoy cabbage, is the Savoy or lettuce-leaved 
spinach. All the species are Asiatic ; the cultivated plant 
was first introduced into Europe by the Arabs by way of 
Spain. 
2. One of several other plants affording a dish 
like spinach. See phrases below Australian 
spinach, a species of goosef oot, Chenopodium an ricom urn. 
a recent substitute for spinach ; also, Tetragonia implexi- 
coma, the Victorian bower-spinach, a trailing and climbing 
plant festooning bushes, its leaves covered with transpa- 
rent vesicles as in the ice-plant Indian spinach Same 
as*fa(ooar nightshade. See nightshade. Mountain spin- 
ach. See mountain spinach. New Zealand spinach, a 
decumbent or prostrate plant, Tetragonia ezpansa, found 
in New Zealand, Australia, and Tasmania, and also in Ja- 
pan and southern South America. It has numerous rhom- 
5834 
bold thick and succulent deep-green leaves. Straw- 
berry spinach. Same as strawberry-Mite. Wild spin- 
ach, a mime of several plants locally used as pot-herbs, 
namely Chenopodium Komu-Jlenriau and C. album, Beta 
i/iitrtluna (the wild beet), and Campanula latifolia. [Prov. 
Eng.] 
Spinachia (spi-na'ki-ii). H. [NL. (Cuvier, 1817), 
< L. spina, a thorn, prickle, spine : see tspiiu; 
and cf. spinach.'] In ichth., a genus of marine 
gasterosteids. .S. ntlj/nris is the common sea- 
stickleback of northern Europe. 
Spinacia (spi-na'si-a), . [NL. (Tournefort, 
1700), < ML. spinai-iu, "spinach : see spinach.] A 
genus of apetalous plants, of the order Chei/o- 
limliacese and tribe Atriplieex. It is characterized 
by bractless and commonly dioecious flowers, the pistillate 
with a two- to four-toothed roundish perianth, its tube har- 
dened and closed in fruit, covering the utricle and its sin- 
gle erect turgid seed. There are 4 species, all Oriental (for 
which see spinach). They are erect annuals, with alter- 
nate stalked leaves which are entire or sinuately toothed. 
The flowers are borne in glomerules, the fertile usually 
axillary, the staminate forming interrupted spikes. 
Spinacidae (spi-nas'i-de), n. pi. [NL., < Spinax 
(-ac-) + -idee.] A family of anarthrous sharks, 
typified by the genus Xpiiiaj-; the dogfishes. 
There are 6 or more genera and about 20 species of rather 
small sharks, chiefly of the Atlantic. Also called Acan- 
thiidx, Centrinidse, and Spinaces. 
spinacine (spin'a-sin), a. [< Spinax (-ac-) + 
-/(!.] Of or pertaining to the Spinacidae. 
spinacoid (spin'a-koid), a. and n. [< Spinax 
(-ac-) + -oid.] I. a. Resembling or related to 
the dogfish; of or pertaining to the Spinacidse. 
II. H. A member of the Spinacidee; a dog- 
fish. 
spinage, n. See spinach. 
spinal (spl'nal), a. [= F. spinal = Sp. espinal = 
Pg. espinhal = It. spinale, < LL. spinalis, of orper- 
taining to a thorn or the spine, < L. spina, a thorn, 
prickle, spine, the spine or backbone : see spine.'] 
In anat. : (a) Of or pertaining to the backbone, 
spine, or spinal column ; rachidian ; vertebral : 
as, spinal arteries, bones, muscles, nerves; spi- 
nal curvature ; a spinal complaint. (6) Pertain- 
ing to a spine or spinous process of bone ; spi- 
noug : as, the spinal point (the base of the nasal 
spine, or subnasal point): specifically used incra- 
uiometry. [Bare.] -Accessory spinal nerve, or 
spinal accessory. Same as accwtsorius (6). Acute, 
atrophic, and spastic spinal paralysis. See paralysis. 
Spinal arteries, numerous branches, especially of the 
vertebral artery, which supply the spinal cord. Spinal 
bulb, the medulla ohlongata. Spinal canal See ca- 
nali. Spinal column, the spine or backbone ; the ver- 
tebral column or series of vertebrae, extending from the 
head to the end of the tail, forming the morphological 
axis of the body of every vertebrate. In man the bones 
composing the spinal column are normally thirty-three 
seven cervical, twelve dorsal or thoracic, five lumbar, five 
sacral, and four coccygeal. These form a flexuous and 
Spinax 
sacral. Twenty- four of its bones are individually movable. 
The total length averages 26 or 27 inches. See vertebra. 
and cuts under backbone and spine. Spinal cord, the 
main neural axis of every vertebrate, exclusive of the bruin; 
the myelon, or the neuron without the enccphalnn; the 
spinal marrow, or nervous cord which extends in the 
spinal canal from the brain for a varying distance in dif- 
ferent animals, and gives off the series of spinal nerves in 
pairs. The cord is directly continuous with the brain in 
all cranial verte- 
brates, and, with 
the brain, consti- 
tutes the neuron, 
or cerebruspiiiul 
axis, developed 
from an involu- 
tion of epiblast in 
connection with a 
notochord (see cut 
under protoverte- 
bra). The cord is 
primitively tubu- 
lar, and may re- 
tain, in the adult, 
traces of its ccelia 
ri i. nli 
me cora IB Solid 
and SUbcylindri- 
Human Spinal Column. 
A, side view ; Jj, same, in median sagittal section ; C, front view ; 
c, seven cervicals ; rf, twelve dorsals ; /, five lumbars ; s, five sacrals, 
fused in a sacrum ; cd, four caudals or coccygeals, forming a coccyx. 
flexible column capable of bending, as a whole, in every 
direction. It is most movable in the lumbar and cervical 
regions, less so in the dorsal and coccygeal, fixed in the 
(see rhoinbocoetia), Cross-section of Human Spinal Cord. 
comparable to the AC, anterior column ; AF, anterior fissure ; 
CO2lfaeof the brain; AGC. anteriorgray commissure; AH, anterior 
but it generally horn of gray matter; AR. anterior roots; A! . 
nlMlflu/. n Bending anterolateral tract, or tract of 
solidities, and also Cowers; BC, postero-extcmal column, or col- 
becomes UUted, or umn of Burdach ; Can., central canal ; cc. 
presents several Clarke's column; CPT, crossed pyramidal 
parallel columns, "*"' " cerebellar tract; upr. direct or 
* uncrossed pyramidaltract; DT, antcrolatera] 
' descending tract ; GC. posteromedian column, 
certain Of Which or column of Goll; I., I.tssauer's tract: LC. 
the spinal nerves lateral column ; in. lateral horn or inter- 
Tn man mediolateral tract of gray matter with con- 
tainedBanglion-cells: PC. posterior column! 
PF| posterior fissure; PGC, posteriorgraycom- 
missure; PR. posterior root; SG, subst.mti.i 
cal, and extends gelatinosa ; we, anterior white commissure. 
in the spinal ca- 
nal from the foramen magnum, where it is continuous 
with the oblongata, to the first or second lumbar vertebra. 
It gives off the spinal nerves, and may be regarded as made 
up of a series of segments, from each of which springs a 
pair of nerves ; it is divided into cervical, thoracic, lum- 
bar, sacral, and coccygeal regions, corresponding to the 
nerves and not to the adjacent vertebrae. There is an en- 
largement where the nerves from the arms come in (the 
cervical enlargement), and one where those from the legs 
come in (the lumbar enlargement). A cross-section of the 
cord exhibits a central H-shaped column of gray substance 
incased in white. (See figure.) The tracts of different 
functions are exhibited on one sideof the cut; they are not 
distinguished in the adult healthy cord, but differ from one 
another in certain periods of early development, and may 
be marked out by secondary degenerations. The cord is 
a center for certain reflex actions, and a collection of path- 
ways to and from the brain. The reflex centers have been 
located as follows : scapular. 5 C. to 1 Tli. ; epigastric, 4 
Th. to 7 Th. ; abdominal, 8 Th. to 1 L. ; cremasteric, 1 L. 
to 3 L ; patellar, 2 L. to 4 L. ; cystic and sexual, 2 L. to ' 
4 L. ; rectal, 4 L. to 2 S. ; gluteal, 4 L. to 6 L. ; Achilles ten- 
don, 5 L. to 1 8. ; plantar, 1 S. to 3 S. See also cuts under 
brain, cell, Petromyzontidae, and Pharynffobranchii. Spi- 
nal epilepsy, muscle-clonus, spontaneous or due to as- 
suming gome ordinary position of the legs, the result of 
increased myotatic irritability, as in spastic paralysis. 
Spinal foramina, the intervertebral foramina. Spi- 
nal ganglia. See ganglion. Spinal marrow. Same 
as smnal cord. Spinal muscles, the muscles proper 
of tne spinal column, which lie longitudinally along 
the vertebrae, especially the epaxial muscles of the back, 
constituting what are known in human anatomy as the 
third, fourth, and fifth layers of muscles of the back 
(the so-called first and second "layers "of human anatomy 
being not axial, but appendicular). One of these is called 
spinalis. Spinal nerves, the numerous pairs of nerves 
which arise from the spinal cord and emerge from the in- 
tervertebral foramina. In the higher vertebrates spinal 
nerves originate by two roots from opposite sides of that 
section of the spinal cord to which they respectively per- 
tain a posterior, sensory, or ganyli&nated root, and an an- 
terior, motor, or non-ganglionated root, which usually unite 
in one sensorimotor trunk before emergence from the 
intervertebral foramina, and then as a rule divide into two 
main trunks, one epaxial and the other hypaxial. The 
number of spinal nerves varies within wide limits, and 
bears no fixed relation to the length of the spinal cord, 
which latter may end high in the dorsal region, yetgive off 
a leash of nerves (see cauda equina, under cauda) which 
emerge from successive intervertebral foramina as far as 
the coccygeal region. The spinal nerves form numerous 
and intricate connections with, the nerves of the gan- 
glionic system. Their epaxial trunks are always few and 
small in comparison with the size, number, and extent of 
the ramifications of the hypaxial trunks, which latter 
usually supply all the appendicular and most of the axial 
parts of the body. Spinal reflexes. See reflex. Spi- 
nal veins, the numerous veins and venous plexuses in 
and on the spinal column, carrying off blood from the 
bones and included structures. In man these veins are 
grouped and named in four sets. See vena. 
spinalis (spi-na'lis), n. ; pi. spinales (-lez). [NL. 
(sc. muscitlus), < LL. spinalis, pertaining to a 
thorn: see spinal.] In anat., a series of muscu- 
lar slips, derived from the longissimus dorsi, 
which pass between and connect the spinous 
processes of vertebrae: usually divided into 
the spinalis dorsi and spinalis colli, according to 
its relation with the back and the neck respec- 
tively. 
spinate (spi'nat), a. [< NL. itpinatus, < L. 
spina, spine : see spine. Cf. spinach (d).~] Cov- 
ered with spines or spine-like processes. 
Spinax (spi'naks), n. [NL. (Cuvier, 1817), < Or. 
airiva or o-jr/wy, a fish so called.] A genus of dog- 
fishes, giving name to the family Spinadda?, and 
