diphtheria 
Diphtheria is not an hereditary disease; but a special 
aptitude to receive and develop the poison evidently per- 
tains to certain individuals and families. 
Quain, Med. Diet., p. 375. 
diphtheritic (dif- or dip-the-rit'ik), . [< diph- 
theritis + -ic.~] Of the nature of, pertaining or 
relating to, or affected by diphtheria : as, diph- 
theritic laryngitis ; a diphtheritic membrane ; a 
diphtheritic patient. 
diphtheritically (dif- or dip-the-rit'i-kal-i), 
adv. In the manner of diphtheria ; with regard 
to diphtheria. 
Do the violent reactions of the tonsils of these persons 
to weather changes involve likelihood of rendering them 
diphtheriticalli/ infectious? Sanitarian, XVII. 202. 
diphtheritis (dif- or dip-the-ri'tis), . [NL., 
< Gr. itiflepa, a prepared skin (membrane) (see 
diphtheria), + -itis.] Same as diphtheria. 
diphtheroid (dif- or dip'the-roid), a. [< diph- 
theria + -aid] Resembling diphtheria. 
1630 
diphthong (dif- or dip'thong), . [Formerly dlphycercy (difi-ser-si), . [As diphycerc + 
also dipthong; = F. dfohtoonffue = Pr. diptonge -/.] The state of being diphycercaL 
= Sp diptonqo = p g .(iipitth<m g o,<Ktongo = It. Diphydse, Diphydes (dif 'i -de, -dez), n. pi. 
dittonqo = D. diphthongs = Gr. diphthong = [NL.] Same as Diphyida; 
Dan. Sw. dif ton g, < LL. diphthongus, < Gr.A'^oy- Diphyes (dif i-ez), n. [NL. (Cuvier, 1810, < 
roc, also ttiflovyov, a diphthong, fern, and neut. Gr. St^s, of double nature or form, < it- two-, 
respectively of i'uflorm, with two sounds, < it-, 
two- + <*0oyyoc, voice, sound, < ^eyyecdat, utter 
A coalition or union of two vowels 
pronounced in one syllable. In uttering a proper 
diphthong both vowels are pronounced ; the sound is not 
simple, but the two sounds are so blended as to be consid- 
ered as forming one syllable, as in joy, noise, bound, out. 
An ' ' improper " diphthong is not a diphthong at all, being 
merely a collocation of two or more vowels in the same 
syllable, of which only one is sounded, as ea in breach, eo 
in people, ai in rain, eau in beau. (See digraph.) In Greek 
diplanetism 
genus of phytophagous tetramerous beetles, of 
the family Clirysomelida>.2. A genus of lamel- 
licorn beetles, of the family Scarabaiidce. 
Diphyllodes (dl-fi-16'dez), n. [NL. (Lesson, 
1835),< Gr. <5(-,two-, + QV'A'AOV, leaf, + eliof, form.] 
A genus of 1'aradiseida;, containing the mag- 
nificent bird of paradise, I), speciosa or magni- 
fied : so called from the bundle of long, silky, 
yellow plumes oil the nape. Another species, 
D. wilsoni, is sometimes placed in this genus. 
diphyllous (di-fil'us), a. [< Gr. it-, two-, + 
ytMav = Ij. folium, a leaf, + -OM.S.] Having two 
leaves: said of a calyx formed of two sepals, etc. 
diphyodont (dif i-o-dont), a. and . [< NL. di- 
pl<yodon(t-)s, < Or. iiijmfff, of double form, two- 
fold (see Diphyes), + bdovf (Movr-) = E. tooth.] 
Diphycercal Tail of Spotted Burbot (Lota macuiosa). I. a. Having two sets of teeth, as a mammal; 
Whatever the condition of theextreme end of the spine F*^j2 SZn^nd toThf ammat 
,f a fish it occasionally retains the same direction as the to the system ot dentition and to trie animals 
trunk part, but is far moreigenerally bent up. ... In the which have Such a system : opposed to mo- 
' nophyodontanApolyphyodont. See II. 
In the Marsupialia the diphyodont condition is in a rn- 
dimentary stage, for it is confined to one tooth only on 
either side of the jaw. 
Oegenbaur, Comp. Anat. (trans.), p. 562. 
II. . A mammal which has two sets of 
teeth. Most mammals have a definite set of milk-teeth 
which are deciduous, and are displaced and replaced by a 
permanent set. The latter, as a" rule, differ both numeri- 
cally and otherwise from the former, particularly in the 
appearance of true molars, which are lacking in the milk- 
dentition. Thus, in a child there are 20 teeth, none of 
them molars proper ; in the adult there are 32, an in- 
crease of three molars above and below on each side. 
- - diphyozooid (dif"i-o-zo'oid), n. Same as di- 
(dif i-id), n. One of the Diphyidai. phyzomd. 
Each group of individuals [in the Calycophora} consists diphysite (dif 'i-Slt), n. [< Gr. it-, two-, + <t>vat, 
of a small nutritive polyp, a tentacle with naked Jiidney- nature, + -ite 2 . ] One who held the doctrine of 
+ #*, produce, < fveaBat grow.] The typical 
genus of the family JJtphytdai. D. amminata, a 
& ** ***"** " 
, , 
grammar, a proper diphthong is a diphthong th e first vowel 
of which is short ; an improper diphthong, a diphthong the 
first vowel of which is long. The proper diphthongs are 
at, i, 01, ov, ew, ov ; the improper, at, 171, wt (commonly 
written a, 77, w : see iota subscript, under subscript), TJV, <av. 
' 
become free and assume a separate existence as Eudoxia. 
Claus, Zoology (trans.), I. 249. 
- j- v, Diphyidae (di-fl'i-de), n. pi. [NL., < Diphyes + 
theimpJ P t P ^T,^ h (comm 8 n^ ^ A 'family of sipWophorous Veanic 
to subscript, under subscript), vv, <uv. hydrozoans, of the order Calycophora, having a 
An improper 'diphthong not usually distinguished as such 
is &v, as in ^aOi, Epic rijJi. Some include m in this class, 
and some limit the term to n, TJ, <? 
Whether there were any true diphthongs in Old-Eng- 
lish, and if not, when they were introduced, is a question 
which cannot now be answered. 
G. P. Marsh, Lects. on Eng. Lang., xxii. 
diphthongal (dif- or dip-th&ng'gal), a. [< diph- 
thong + -al.] Belonging to a diphthong ; con- 
sisting of two vowel-sounds pronounced in one 
syllable. 
To the joint operation ... of these two causes, uni- 
versal reading and climatic influences, we must ascribe 
our habitof dwelling upon vowel and diphthongal sounds. 
G. P. Marsh, Lects. on Eng. Lang., xxx. 
drOhthOngallV (dif- Or dip-thong gal-l), adV. In calyx. K. Distal nectocalyx. with a bristle, a, through the canal tra- 
*^T , 77 & f x vl >r.H hvthc hvrlrrximna m A. C. Fxtremitv of distal nectocalvx. 
a diphthongal manner. 
diphthongation (dif- or dip-thong-ga'shon), n. 
[= F. diphthongaison; as *diphthongate, equiv. 
to diphtliongize, < diphthong + -ate 2 : see -ation.] 
In philol., the formation of a diphthong; the 
shaped groups of nematocysts, and gonophores. To these j'-.i,-,.-^,,,,, A^srv irrmrnnprlv dionlnititf 
is usually added a funnel or umbrella-shaped hydrophyl- dipnysitism. Also improperly awpliysne. 
These groups of individuals may in some .diphyids dlphySltlSm (dif l-Sl-tizm), TO. [< diphysite + 
-ism.] In theol., the doctrine of two distinct 
natures in Christ, a divine and a human, as 
opposed to monophysitism. According to the usual 
view, these two natures coexist in one person, whereas the 
Nestorians affirm the existence of a distinct person for 
each nature. Also improperly diophysittem. 
diphyzooid (dif-i-zo'oid), n. [< Gr. iupvf/f, of 
double form (see Diphyes), + zob'id.] A repro- 
ductive zooid . 
of the oceanic 
hydrozoans of 
the order Ca- 
lycophora, de- 
tached and 
free-swimming 
by means of 
its nectoca- 
lyx, represent- 
ing the com- 
plex distal 
set of appen- 
dages. Alsorfi- 
phyozoiiid. 
The distal set 
A. Dipliyts appendictilata : n, hyili.inth* and hydrophyllia on 
the hydrosoma or ccenosarc ; b, proximal nectocalyx ; c, aperture of 
distal nectocalyx ; d, somatocyst ; e, the prolongation of the distal 
nectocalyx, by which it is attached to the hydrosoma ; f, point of at- 
tachment of the hydrosoma in the hydrcecium of the proximal necto- 
/ersed by the hydrosoma m A. C. Extremity of distal nectocalyx 
with its muscular velum. (All slightly enlarged.) 
pair of large swimming-bells or nectocalyces 
opposite each other on the upper part of the 
stem. It is represented by the genera Diphyex and Abyla. 
by adding another vowel : as, Greek ^aiv-etv. 
from root *(j>av; French rien, from Latin rem; Dip 
Italian fuoco, from Latin focus, and the like. ' 
diphthongic (dif- or dip-th6ng'ik), a. [< diph- 
conversion of a simple vowel into a diphthong $%"%*%$$$ or wj^ f*S 
under diphyzooid. 
(a'(di-fil'a), n. [NL., < Gr. it-, two-, + 
= L. folium, leaf.] A genus of true 
_, __ , , ,, blood-sucking or vampire bats of the warmer 
thong + -ic.] Pertaining to or of the nature parts of America, composing with Desmodus ,,! n-,,i,,,,,",' (cik>&i)\~~a.~e. gonophore, or reproductive 
of a diphthong. f he grO up Desmodontes of the family Pkyllo- L this condition ^^ t ^^ ! S^S^^ 
diphthongization (dif- or dip ''thong- i-za- stomatidte, differing from Desniodm in having they grow and al- brium.o. 
snon), n. [< diphthongize + -ation.] Same as one molar in each Jaw, an " 
diphthongation. Also spelled diphthonyisation. modus. Spix, 1823. 
The diphthongaation of 6 into ie. JEncyc. Brit. Diphyllidat) (di-fil'i-de), n. pi. [NL., < Gr.^A-, 
of appendages [in 
the calycopho- 
raus] is the old- 
est, ami, as they at- 
tain their full de- 
velopment, each 
set becomes de- 
tached, as a free- 
swimming com- 
andacalcar. See Des- *f:"''*"d 
A. B. DiphyzoOid (Sphtneides), lateral 
d front views. C. Diphyzooid of Abyla 
. . , 
, containing ova. (AH enlarged.) 
Huxley, Anat. Invert., p. 131. 
dinhthoTifrizp (dif or dit>'th6nsr iz) v nret two ^ + W^* a lea (cf.~-y)%Ka), + -ida;.] Dipina (di-pi'iift), n. pi. Same as Dipodida;. 
aSd vv dhfhtll .noted Sr d^hthonatzina K A fami1 ^ of cestoid flatworms . or tapeworms, diplacanthid (dip-la-kan'thid), a. Having bi- 
and pp. diphthongized^ ppr. diphthongizing. \ . They have a clrclet o( hooklets 011 the neck ^ two pe . ^J adambulacral spines, as a starfish; spe- 
dunculate unarmed suckers or facets on the head, whence ciflcall p e rta ining to or having the characters 
U-, _ 
diphthong + -ize.~] I. trans. To change, as a 
vowel, into a diphthong: thus the u of many 
Anglo-Saxon words has been diphthongized -[^'"i" 11 , 8 . 6 /!' 
into ow in modern English, as in the word now. Dlphyllldea . 
A tendency to diphthonr/ise vowels in general. phyll-Ma? + -id-ea 
Amer. Jour. Philol., V. 615. 
II. intrans. To unite in forming a diphthong. 
This second (J) may diphthongize with any preceding 
vowel. J. Hadley, Essays, p. 251. 
the name. It is represented by the genus Echinobothrium -. . , _ 
of the Diplacantlnda. F. J. Bell. 
(dif-i-lid'e-a), n. pi. [NL., as Di- Diplacanthida(dip-la-kan'thi-da),.^. [NL., 
id-ea.] A'divisionof the Cestoidea, as Diplacanthus + -ida.'] Those echinoids 
or cestoid worms, including those tapeworms which have biserial adambulacral spines. F. 
which when adult have parts or organs of the J. Bell. 
head in pairs, as two suckers and two rostellar Diplacanthus (dip-la-kan'thus), . [NL., < Gr. 
ees: they have also a collar of hooklets (W/ldof, double (see diploe), + aKavOa^a, spine.] 
eminences: ,,*.*.. - - 
on the neck. A genus of fossil fishes of the Old Red Sand- 
Also spelled diphthongise. Diphyllidia (dif-i-lid'i-a), n. [NL. ; cf. Diphyl- stone, having a heterocercal tail, very small 
diphycerc (dif i-serk), a. [Irreg. < Gr. <!<0wfc, lidea.] A genus of nud'ibranchiate gastropods : scales, and two dorsal fins, each with a strong 
of double nature or form (see Diphyes), + Kip- a synonym of Pleurophyllidia (which see). spine, whence the name. Agaxxi'. 
KOf, tail.] Same as diphycercal. diphyllidiid (dif-i-lid'i-id), . A gastropod of diplanetic (di-pla-net'ik), a. [< Gr. <5;-, two-, 
diphycercal (dif-i-ser'kal), a. [< diphycerc + the family Diphyllidiidce. twice, 4- irAavr/rtK^, disposed to wander, < ir/la- 
-(.] In ichth., having tne tail symmetrical, or Diphyllidiidae (di-fil-i-di'i-de), n. pi. [NL., r;/r<Sf. wandering: see planet.] In cryptogamic 
consistingof equal upper and lower halves, with < Diphyllidia + -idee.] A f amily of nudibran- bot., having two periods of activity separated 
respect to the bones which support it, the end chiate gastropods, typified by the genus Diphyl- by one of rest, as the zoospores of certain gen- 
of the spinal column or the notochord not be- lidia: synonymous with PUurophyllidiida;. era of Saprolct/>iic: 
ing bent upward as is usually the case in fishes. Diphyllocera (dif-i-los'e-ra), re. [NL. , < Gr. A-, diplanetism (di-plan'e-tizm), n. [< di/>l(tne1-if 
See homocercal, hypural, heterocercal. two-, + <j>vl.?Mv, a leaf, "+ '\-fpaf, horn.] 1. A + -ism.] In cryptogamic bot., the property of 
