s Hippocastattvm, 
a, flower ; *. seed ; c, seed cut longitudinally. 
aesculin 
aesculin, aesculine. See cseulin, csculim: 
^SCUlus (es'ku-lus), n. [L., the Italian oak: 
see esculin, etc.! A genus of trees and shrubs, 
natural order 
Sapindacia, 
chiefly North 
American, with 
broad digitate 
leaves and 
showy flowers 
in large pani- 
cles. The seeds 
are large, of the 
shape and color 
of chestnuts, but 
too bitter to be 
eaten. The timber 
is of little value. 
The horse-chest- 
nut, ^E. Hipjtocas- 
tanum, supposed 
to be originally 
from northern In- 
dia, is very exten- 
sively cultivated 
as an ornamental 
shade-tree, and the 
fruits are used in 
southern Europe 
for feeding sheep 
and horses. The 
American species, growing in the western and southern 
United States, have the popular name buckeye (which see). 
(esh'nji), n. See JEschna. 
(a'ser, Ic'el. pron. a'sir, mod. I'sir), n.pl. 
[Icel., nom. pi. of ass, a god: see As 3 .] The 
collective name for the gods of Scandinavian my- 
thology. There were twelve gods and twenty-six god- 
desses, dwellers in Asgard. See Asffard. 
aesnecy, . See esnecy. 
.dSsopian (e-so'pi-an), a. [< L. JEsopius, < JEso- 
pus, Gr. Aio-o;rof, ^Esop.] Pertaining to ^sop, 
an ancient Greek writer of fables, of whom lit- 
tle or nothing is certainly known ; composed by 
him or in his manner: as, a fable in the JEso- 
pian style. Also spelled Esopian. 
aestates (es-ta'tez), n. pi. [L., freckles, pi. 
of tgsta(t-)s, summer, summer heat: see esti- 
val.] In med., heat-spots; freckles; sunburnt 
patches. 
aesthematology, . See esthematology. 
aesthesia (es-the'si-a), n. [NL., < Gr. . 
perception by the senses, < aiaffdveaOai, perceive 
by the senses.] Perception; feeling; sensa- 
tion; sensibility: the opposite of anesthesia 
(which see). Also written esthesia, (esthesis, 
esthesis. 
aesthesiogen, aesthesiogenic, etc. See esthe- 
siogen, etc. 
acsthesiology, aesthesiometer, etc. See esthe- 
siology, etc. 
aesthesis (es-the'sis), . Same as aesthesia. 
Also spelled esthesis. 
aesthesodic, aesthete, etc. See esthesodic, etc. 
aestiferous, aestival, etc. See estiferous, etc. 
^Estrelata, . See (Estrelata. 
aestuancet (es'tu-ans), n. [< L. cestuan(t-)s, ppr. 
of aestuare, burn," glow: see cestuate.] Heat; 
warmth: as, "regulated estuance from wine," 
Sir T. Browne. Also spelled estuance. 
aestuary (es'tu-a-ri), . ; pi. actuaries (-riz). [< 
L. testuarium,' a vent-hole for vapors, also an 
estuary, < aistuari, rage, burn, be warm: see 
estuary. ] 1 . A vapor-bath, or any other means 
for conveying heat to the body. 2. See estuary. 
cBstuatet (es'tu-at), v. i. [< L. (estuatus, pp. of 
a-stuare, burn, glow, rage, boil up, < tcstus, a 
burning, glow, fire, surge, etc.: see estuary, 
estival.] To boil ; swell and rage ; be agitated. 
Also spelled estuate. 
aestuationt (es-tu-a'shpn), n. [< L. '(estuatio(n-), 
(.cestuare: see testuate.'] Aboiling; agitation; 
commotion of a fluid; hence, violent mental 
commotion; excitement: as, " estuations of joys 
and fears," Mountague. Also spelled estuation. 
aesturet (es'tur), n. [Irreg. < L. cestuare, be in 
commotion, boil, rage, etc., as if for asstiis, 
surge, billows: see actuate.] Violence; com- 
motion. Also spelled esture. 
The seas retain 
Not only their outrageous cesture there. 
Chapman, Odyssey, xii 111. 
aet., aetat. [Abbrev. of L. cetatis, gen. of eeta(t-)s, 
age: see age and eternal.] Of the age; aged: 
chiefly used in classic or scholarly epitaphs or 
obituaries, whether composed in English or in 
Latin: as, 06. 1880, cst. (or cetat.) 70: in full 
Latin, oUit [anno Domini] MDCCCLXXX, [an- 
no] aetatis (sua;) LXX; that is, he (or she) died 
in (the year of the Lord) 1880, in the seventieth 
year of his (or her) age (but usually taken as 
"70 [full] years of age," "aged 70"). 
96 
(e-te'a), n. [NL. ; origin not obvious.] 
The typical genus of ^teida;. JE. anijuinca is 
known as snake-coralline. Also written *-Eta. 
JEteidlS (e-te'i-de), n. pi. [NL., < JEtea + -idee.] 
A family of chilostomatous polyzoans, typified 
by j&tea, erect and free or decumbent and 
adherent, uniserial, with subterminal mem- 
branous area and tubular zooscia. Also writ- 
ten jEtiitif. 
jEthalium (e-tha'li-um), n. [NL.,< Gr. aWafof, 
smoke, soot ; with ref . to the abundant dust-like 
spores. Cf. Fuligo, an allied genus, < ii.fuligo, 
soot.] 1. A genus of Myxontycetes, or slime- 
molds, forming thick cake-like receptacles cov- 
ered by a brittle cortex, and closely adherent 
to the surface on which they grow. They are 
often found in hothouses where spent tan is used for heat- 
ing purposes, and hence are sometimes called flowers of tan. 
2. [I. c.] A similar receptacle in any genus: 
with a plural, cethalia (-&). 
aetheling, . See atheling. 
aetheogam (a-e'the-6-gam), n. [< Gr. /%, 
unusual (< a- priv. + rfiof, custom: see ethic), + 
ya/jof t marriage.] In De Candolle's system of 
classification, a plant belonging to a group of 
cryptogams which were the only ones of the 
order tnten known to have sexual organs, includ- 
ing the Equisetaceae, Filices, Musci, higher Hepa- 
ticce, etc. 
aetheogamons (a-e-the-og'a-nms). a. Belong- 
ing to the aetheogams. 
aether, n. See ether 1 . 
-Sltheria (e-the'ri-a), n. [NL., appar. named 
from the brilliancy of the interior surface, < L. 
(Ptlterius, < Gr. aiSeptof, 
of the ether or upper 
air, heavenly, ethe- 
real : see ethereal.] A 
genus of bivalve mpl- 
lusks, of the family 
Unionidce, found in the 
rivers of Africa and 
Madagascar ; river- 
oysters. The exterior is 
rugged, but the interior 
of the valves is pearly, of 
a vivid green color, and 
raised in small blisters. 
The natives of Nubia adorn their tombs with them. Also 
spelled Ethfria, as originally by Lamarck, 1808. 
aetheriid (e-the'ri-id), n. A bivalve mollusk of 
the family dStheriidee. 
j theriidse (e-the-ri'i-de), n. pi. [NL., < M(he- 
ria + -idle.] A family of mollusks, of which 
JEtlieria is the typical genus. Also written Mthe- 
rioidoe, jEtheridai, dStheriadce, and Etheridai. 
jUthiop, -flJthiopiant. See Ethiop, Ethiopian. 
aethippst (e'thi-ops), n. [NL., after L. JEthiops, 
Ethiopian : see Ethiop.] An old pharmaceuti- 
cal term applied to several mineral prepara- 
tions of a black or nearly black color. Also 
spelled ethiops JEthiops martial [< L. martialin, of 
Mars, i. e., of iron], black oxid of iron. JEthiops min- 
eral, black sulphid of mercury, prepared in the laboratory. 
aethogen (e'tho-jen), n. [< Gr. alBof, a burning 
heat (see ether), + -yevljf, taken as 'produ- 
cing': see -gen.] Nitrid of boron; a white, 
amorphous, tasteless, inodorous powder, insol- 
uble in water, infusible, and ncrn-volatile. 
Heated in an alcohol-flame fed with oxygen, it burns 
rapidly with a faint greenish-white flame. Watts. 
aethrioscope (eth'ri-o-skop), n. [< Gr. aiBpia, the 
open sky (< aldpiof, clear^ fair, in the open air, 
< alBpr/, the open sky, < aifMjp, the sky, the upper 
air, > E. ether), + aiumeiv, observe, look at.] 
An instrument for measuring the minute varia- 
tions of temperature due to different conditions 
of the sky. It consists of a differential thermometer 
(which see, under thermometer), both bulbs of which are 
within a cup-shaped mirror, one of them in its focus, so 
as to be especially affected on being exposed to the sky. 
The cup is kept covered with a lid when the instrument is 
not in use. Its delicacy is so great that it is affected by 
every passing cloud. 
^Ethusa (e-thu'sa), . [NL., < Gr. aiBovaa, fern, 
of alduv, ppr. of aiOetv, burn, blaze : see ether.] 
1. In bot., a genus of umbelliferous plants, of 
a single species, JE. Cynapium, introduced into 
America from Europe, and known as fool's- 
parsley. It is an annual garden-weed, of nauseous and 
deleterious properties, and is sometimes mistaken forpars- 
ley, whence its common name. 
2. In sool., a genus of decapod crustaceans, of 
the family Dorippidee. 
Aetian (a-e'shi-an), . [< LL. Aetius, Gr. 'Af- 
riof, a personal name, < "aeriof, airaoc., aimof, 
of the eagle, < dcrrif, aicrof, eagle.] One of a 
sect -of strict Arians of the fourth century, 
named from their leader Aetius, called the 
Atheist (died in Constantinople, A. D. 367). 
See Eunomian and Anomoean. 
afar 
(e'ti-de), n. /il. Same as 
aetiological, etiological (e"ti-o-loj'i-kal), a. 
[< Gr. <UTKAirruc6f, inquiring into causes : see 
irtioloyy.] Of or pertaining to aetiology ; con- 
nected with or dependent upon the doctrine of 
efficient or physical causes, as distinguished 
from teleological or final causes. 
The practical results of rtii'lo'iii'n/ stmlirs, BO far as the 
prevention and cure of disease are concerned, are likely 
to tie much greater than those which have been gained lij 
the pathologists. ' G. M. Sternbery, Bacteria, p. 230. 
aetiologically, etiologically (e"ti-o-loj'i-k;il-i), 
adv. In an setiological manner; with regard 
to cause, or the assignment of a cause : as, an 
a'tiologically obscure failure of nutrition. 
aetiolqgist, etiologist (e-ti-ol'o-jist), . One 
who is versed in astiologv; one who investi- 
gates physical causes, or inquires into the re- 
lations of such causes to effects in physics or 
biology : often used as the opposite of tele- 
nlof/ist. 
aetiology, etiology (e-ti-ol'o-ji), n. [< LL. eetio- 
logia, < Gr. ainoMyia, statement of the cause 
(cf. aiTio^oytlv, inquire into the cause, account 
for), < atria, cause, + -^.rryia, < Uytiv, speak: 
see -ology.] 1. An inquiry into or a theory 
of the physical causes of any class of phenom- 
ena. 
Morphology, distribution, and physiology investigate 
and determine the facts of biology. ^Etiology has for its 
object the ascertainment of the causes of these facts, and 
the explanation of biological phenomena, by showing that 
they constitute particular cases of general physical laws. 
It is hardly needful to say that aetiology, as thus con- 
ceived, is in its infancy. Huxley, Anat. Invert., p. 37. 
2. Specifically, in med., an inquiry into or ac- 
count of the origin or causes of disease, or of 
a particular kind or case of disease. 
Sometimes written aitiology. 
aetites (a-e-ti'tez), n. [L., < Gr. acrirtK, eagle- 
stone, < de-nif, eagle.] Same as eaglestone. 
-SJtnean, a. See Etnean. 
JEtolian (e-to'li-an), a. and n. [< L; JEtolia, 
<Gr. AiTu/.ia, .lEtolia.] I. a. Relating or per- 
taining to jEtolia, a district of Greece lying 
north of the gulf of Corinth, or to the race who 
anciently inhabited it. jEtolian League, a demo- 
cratic confederation of the tribes of ancient .Ktniia. some- 
times including the people of various neighboring re- 
gions, celebrated for its long successful wars against the 
Macedonians, Acheans, etc. 
II. n. One of the race anciently inhabiting 
The jBtolians, though famous in the heroic 
age, were rude and barbarous as late as the time of the 
Peloponnesian war, and were not even reckoned as Greeks 
till a late period ; but they attained to considerable power 
through their warlike prowess after the time of Alexander 
the Qreat and their gallantry against the invading Oauls. 
aetpmorph (a'e-to-m6rf), n. A member of the 
Aetomorpho! ; a bird of prey. 
Aetomorphae (a*e-to-m6r'fe), n. pi. [NL., < 
Gr. derof, an eagle, + fwpQf/, form, shape.] In 
ornith., the birds of prey ; a group equivalent 
to the Baptorcs or Acdpitres of most authors. 
Named by Huxley in 1867 as a superfamily of the desmog- 
nathous division of the order Carinata, and divided by 
him into the four families of Strigidte, Cathartidce, Gypcc- 
titia!, and dypogeramdae. The characters of the group 
are drawn chiefly from osteology, but are those of the 
Raptorex as commonly understood. 
aetomorphic (a/'e-to-mor'fik), a. Having the 
characters of or pertaining to the Actomorpha; ; 
raptorial, as a bird. 
Aetosauria (a'e-to-sa'ri-a), n. pi. [NL., < Gr. 
drrdf, eagle, + aaiipof, lizard.] An order of 
s:i iii-i:! us represented by the family Aetosauri- 
<he (which see). 0. C. Marxh. 
Aetosauridae (a'e-to-sa'ri-de), n. pi. [NL., < 
Aetonaurus + -idee.'] A f amily of extinct Triassic 
reptiles allied to or of the order of dinosaurians, 
with limbs and dermal armature resembling 
those of crocodilians, the calcaneum produced 
backward, and two sacral vertebrae. O. C. 
Marsh. 
AetOSauTUS (a/e-to-sa'rus), n. [NL.,< Gr. aerof, 
eagle, + aavpof, a lizard.] A genus of extinct 
reptiles, representing the family Aetosauridae. 
aeuia, aevia. In church, music, a contraction 
of alleluia. See halleluiah. 
aeviternalt, aeviternallyt, etc. See eviternaJ, 
etc. 
JEx (oks), it. In zoiil., same as Aix. 
af-. Assimilated form of Latin ad-, also an erro- 
neous form of other prefixes, before /. See ml-. 
aface (a-fas'), prep. phr. as adv. [< a 3 + face.] 
In face; in front. [Rare.] 
afar (a-far'), adv. [< ME. afer, aferre, ofer, 
afar, commonly separated, n fer, a ferr, earliest 
form aferrum, on ferrum (-um is the dat. suf- 
fix), offeor, equiv. in sense to AS. feorran, 
from far: ME. of, from (E. of, prefix a-*), later 
confused with on, a (E. on, prefix o-3) ; feor, 
