tac-au-tac 
and parries rapidly following one another be- 
tween two fencers of very equal skill, pro- 
longed without a point to the credit of either. 
The tac-au tac in the latter sense is practised by masters 
to give pupils quickness of eye and suppleness of wrist, 
and to accustom them to close play. 
Tacca (tak'a), n. [NL. (Forster, 1776), from the 
Malay name.] A genus of plants, type of the 
order Taccacese, distinguished by its fruit, which 
is a berry, commonly three-angled or six-ribbed. 
It comprises nine trop'ical species, of which three are 
American, the others of 
the Old World. They are 
perennial herbs from a 
tuberous or creeping root- 
stock, with large radical 
leaves which are entire, 
lobed, or dissected, and a 
dense umbel of brown, 
lurid, or greenish flowers 
terminating an erect leaf- 
less scape, and involucrate 
with an exterior row of 
herbaceous or colored 
bracts. The numerous in- 
ner bracts are long, fili- 
form, and pendulous, and 
have been erroneously re- 
garded as sterile pedicels. 
T. pinnatiflda, the pia- 
plant or Otaheite salep- 
plant, yields a nutritious 
starch, the South Sea ar- 
rowroot. (See piaZ.) Its 
leafstalks are boiled and 
eaten in China and Cochin- 
China ; in Tahiti they are 
dried and plaited into 
bonnets. Other species, Howenng Plant lTaaf,H. 
thought to be valuable as flo b transverse section of 
starch-plants, occur in the fruit. 
Australia, India, Madagas- 
car, Guinea, and Guiana. Several species were formerly 
separated as a genus Ataccia (K. B. Presl, 1830), having 
entire leaves and a spreading perianth. 
Taccaceae (ta-ka'se-e), n. pi. [NL. (Lindley, 
1835), < Tacca + -accse.] An order of monocoty- 
ledonous plants, of the series Epigynx, closely 
allied to the Amaryllidacese. It is characterized by 
regular flowers with six included stamens, each dilated 
above into an inflexed two-ribbed or two-horned hood 
within which is the sessile anther, and by a. one-celled 
ovary, a minute embryo, and solid albumen. It includes, 
besides Tacca (the type), only the monotypic Chinese go- 
nus Schizocapsa, distinguished by its different fruit a 
three-celled capsule. 
taccad (tak'ad), n. A plant of the order Titcca- 
cese. Lindley. 
taccada (ta-ka'da), n. The Malayan rice-paper 
plant. See rice-paper. 
taceH) An obsolete variant of fasse 2 for tns- 
set. 
tace 2 (ta'se). [L., impv. of tacere, be silent: 
see tacit.'] Be silent __ Tace is Latin for a candle, 
an old formula humorously enjoining, commending, or 
promising silence : probably originating as an evasive ex- 
planation, to unlearned hearers, of ' ' Tace ! " used in enjoin- 
ing silence. 
"Tace, Madam," answered Murphy, "is Latin/or a can- 
dle; I commend your prudence." 
Fielding, Amelia, I. ix. (Dames.') 
tacet (ta'set), v. [L., 3d pers. sing. pres. ind. 
of tacere, be silent : see tacit.] In musical no- 
tation, an indication that the instrument or 
voice in whose part it is inserted is silent for a 
time. 
tac-freet (tak'fre), a. See tack-free. 
tachH, tacheif (tach), n. [Early mod. E. tache, 
< ME. tache, < OF. tache, F. dial. (Genevese) 
tache, a nail, hook (found only in sense of ' an 
instrument of fishing' (a fish-hook ?), in Roque- 
fort), an assibilated form of OF. toque, a nail, 
hook, tack (found only in the sense of 'the 
back of a chimney' (chimney-hook ?) in Roque- 
fort): see tocfci. Cf. tachi, tache^, v.] A hook, 
catch, clasp, or other fastening. 
And thou shalt make fifty taches of gold, and couple the 
curtains together with the taches. Ex. xxvi. 6. 
f, tacheH (tach), *. [< ME. tachen, tac- 
chen, < tache, n., a hook, fastening; partly by 
apheresis from atachen, attach : see tachi, n., 
and attach. Cf. detach.] I. trans. 1. To fas- 
ten; fix in place; affix; attach. 
Thenne loke what hate other any gawle 
Is Inched other tyged thy lymmez bytwyste. 
Alliterative Poems (ed. Morris), i. 464. 
He hadde a litill cheyne of siluer tacched to his arme. 
Merlin (E. E. T. S.), iii. 615. 
2. To seize upon ; take (a thief). Halliwell. 
II. intrans. To make an attack ; deliver an 
assault : with on or upon . 
Telamon hym tacchit on with a tore speire. 
Destruction of Troy (E. E. T. S.), L 6717. 
tach 2 t,tache 2 t,. [ME., also taeh,tacche,tasche, 
tasshe, touchwood ; origin obscure. Cf. touch- 
wood.] Touchwood. 
0152 
Ac hewe fuyr uf a flynt four hundred wynter ; 
Bote thou haue tache [var. tou-e (B)] to take hit with tun- 
der and [var. or(B)] broches [matches], 
Al thy labour is lost. Piers Plowman (C), xx. 211. 
tache 3 t, tatchf (tach), n. [Early mod. E. also 
fetch, tatche; < ME. tache, tacche, tatche, tachche, 
also terhe, tecchc, tetche, < OF. tache, tfiirlti; 
tcchc, also unassibilated tele, teque, a spot, mark, 
hence a stain, blemish, fault, vice, also, in an- 
other point of view, a characteristic mark or 
quality, natural quality, disposition, F. tache, a 
spot, freckle, stain, blemish, = Sp. Pg. tacha, a 
blemish, blur, defect, = It. tacca, a stain, de- 
fect; prob. a transferred use from 'a mark 
made by a nail' (cf. Sp. tacha, a crack, flaw, = 
It. taccii, a notch, cut), from the orig. sense 'a 
nail, tack': see tack 1 , tach 1 . The more mod. 
form would be tatch, with a reg. var. fetch. 
Hence techy, tetchy, touchy.'] 1. A spot; mark. 
2. A moral spot or stain ; a blemish ; defect ; 
vice. 
Ac I fynde, if the fader be false and a shrewe, 
That somdel the sone shal haue the sires tacches. 
Piers Plowman (B), ix. 146. 
Be not to kynde, to kepynge, & ware knaues tacches. 
Book of Precedence (E. E. T. S.), p. 66. 
All ... children ... are to be kepte diligently from 
the herynge or seynge of any vice or euyl tache. 
Sir T. Elyot, The Governour, i. 4. 
3. A characteristic ; a habit ; disposition. 
Teteh'e or maner of condycyone (tecche, K. teche, S. tetche, 
maner or condicion . . .). Mos, condicio. 
Prompt. Parv., p. 487. 
A chyldis latches in playe shewe playnlye what they 
meane (mores pueri inter ludendum). 
Uorman, Vulgaria, quoted in Prompt. Parv., p. 487. 
Of the maners, tacches, and condycyiouns of houndes. 
US. Sloane, 3501, c. xi., quoted in Prompt Parv., p. 487. 
tache 3 t, tatcht (tach), v. t. [< ME. tachen, tac- 
chen, < OF. tacher, spot, stain, blemish, < tache, 
a spot: see tache 3 , n.] 1. To spot; stain; blem- 
ish. 
If he be tachyd with this inconuenyence, 
To dysdayne others counseyll and sentence, 
He is vnwyse. Barclay, Ship of Fools, I. Iviii. 11. 
2. To mark ; characterize : only in the past 
participle. 
He hath a wif that is a gode woman and a wise, and the 
trewest of this londe and beste tacched of alle gode condi- 
ciouns. Merlin (E. E. T. S.), i. 88. 
tache 4 (tash), n. [A mod. technical use of F. 
tache, a spot, freckle : see tache 3 .] In med. : (a) 
A natural patch or spot of different coloration 
on the skin; a freckle. (6) A local morbid dis- 
coloration of the skin; a symptomatic blotch. 
Taches cerebrales, spots of hyperemia following com- 
paratively gentle stimulation of the skin, as when it is 
stroked. They occur in certain affections of the nervous 
system. 
tache 5 (tach), n. [Also teache; < Pg. tacha, a 
sugar-pan.] Any one in a battery of sugar- 
pans; particularly, the smallest of the series, 
immediately over the fire, also called the strik- 
ing-tache. E. H. Knight. 
tache'H, '* A Middle English variant of toss 2 . 
tachementt, " [ME., by apheresis from atache- 
ment, mod. E. attachment.] An attachment; a 
fixture ; an appurtenance. 
I 3if the for thy thyjandez Tolouse the riche, 
The tolle and the tachementez, tavernez and other. 
Morte Arthure (E. E. T. S.), 1. 156S. 
tacheometer (tak-e-om'e-ter), n. Same as 
tachometer and tachymeter. 
tacheometry (tak-e-om'e-tri), . Same as ta- 
chometri/ and tachymetry. 
tachhydrite (tak'hr'drit), . [< (Jr. raxfc, 
swift, + vSup (v6p-), water, + -tfe 2 .] A massive 
mineral of yellowish color found in the salt- 
mines of Stassfurt in Prussia. It is a hydrous 
chlorid of calcium and magnesium : named in allusion to 
its rapid deliquescence on exposure to the air and water. 
Tachina(ta-ki'na),. [NL.(Meigeu,1803),< Gr. 
*<'f, swift.] A genus of parasitic dipterous 
insects, typical of the family Tachinidse. They 
are mainly parasitic upon caterpillars, upon which they 
lay their white oval eggs and within which their larva? feed. 
They are active, gray, moderately hairy flies, resembling 
the common house-fly. Many species are known, of which 
more than 30 inhabit the United States. T. grotm is a 
large European fly of bristling aspect, black and yellow, 
about two thirds of an inch long. 
tachina-fly (ta-ki'na-fli), . One of the para- 
sitic dipterous insects of the family Tachinidee. 
The red-tailed tachina-fly is Exorisla, leucanias. a common 
parasite of the army-worm and other caterpillars in the 
United States. See cuts under Exorista, Lydella, and 
flemorsea. 
tachinarian (tak-i-na'ri-au), a. and n. [< Tachi- 
naria + -an.] I. a. Of or pertaining to the 
dipterous family Tachinidie, formerly called 
Tachinaria. 
II. n. A tachina-fly. 
Tachyglossa 
taching-end (tach 'ing-end), n. [< tachiiiy, ppr. 
of tach 1 , v.] The waxed thread, armed with a 
bristle at the end, used by shoemakers. Halli- 
well. [Prov. Eng.] 
tachinid (tak'i-nid), a. and n. Same as tachi- 
iiaiinn. 
Tachinidae 1 (ta-kin'i-de), v. pi. [NL., < Tachi- 
iia + -idie.] A family of flies, of which Tachina 
is the typical genus; the tachina-flies. They are 
thick-set^ usually sober-colored, bristly flies of small or 
moderate size, quick in their movements, and frequent- 
ing flowers and rank vegetation. They are parasitic main- 
ly upon lepidopterous larva), but also attack the larvae of 
Orthoptera, earwigs, beetles, some Ilymenoplera, and iso- 
pod crustaceans, and have been known to infest turtles. 
The forms are very numerous, and in America are almost 
wholly unnamed. See cuts under Exorista, Lydella, and 
Nemoriea. 
Tachinidae 2 (ta-kin'i-de), n. pi. [NL., < Tachi- 
nits + -idee.] A family of rove-beetles, of which 
Tachimts is the typical genus, now merged in. 
Staphylinidse. They are small and very agile 
beetles, found on flowers. 
Tachinus (ta-kl'nus), n. [NL., < Gr. raxvt, 
swift.] The typical genus of the coleopterous 
family Tachinidse : so called from their agility. 
tachometer (ta-kom'e-ter), n. [Also tacheome- 
ter; < Gr. raxo'f, swiftness, speed (< ra^vf, swift, 
fleet), + iiirpov, measure.] An instrument for 
measuring velocity. Specifically (o) A contrivance 
for indicating small variations in the velocity of machines, 
one form of which consists of a cup and a tube opening 
into its center, both being partly filled with mercury or a 
colored fluid, and attached to aspindle. This apparatus is 
whirled round by the machine, and the centrifugal force 
produced by this whirling causes the mercury to recede 
from the center and rise upon the sides of the cup. The 
mercury in the tube descends at the same time, and the 
degree of this descent is measured by a scale attached to 
the tube. The velocity of the machine being lessened, the 
mercury rises in the center, causing a proportionate rise 
in the tube, (b) An instrument for measuring the velocity 
of running water in rivers, etc., as by means of its action 
on a flat surface connected with a lever above the surface 
carrying a movable counterpoise, or by its action on the 
vanes of ft wheel, whose revolutions are registered by a 
train of wheelwork ; a current-measurer, (c) An instru- 
ment for measuring the velocity of the blood in a vessel. 
Also hemotachometer. 
tachometry (ta-kom'e-tri), B. [As tachometer 
+ -y3.] Scientific use of the tachometer, in 
any sense. Also tacheometry. 
tachyt, a. [<fac/i 3 + -y 1 .] Vicious; corrupt. 
With no less furie in a throng 
Away these tachie humors flung. 
Wit and Drollery. (Nares.) 
Tachybaptes (tak-i-bap'tez), . [NL. (Reich- 
enbach, 1 849, as Tachybaptus), < Gr. raxi'f, swift, 
+ jiavru, dive, dip.] A genus of very small 
grebes, with short obtuse bill, short tarsi, and 
no decided crest or ruff; the least grebes, or 
dabchicks, of both hemispheres. The type is the 
common European dabchick, T. minor (oifluviatilis). The 
American representative is T. dominicu8(ordominicanut), 
St. Domingo Grebe (Tachybaptes dotninicns). 
the St. Domingo grebe, of the West Indies and other warm 
parts of America, north to the Rio Grande and some parts 
of California ; it is 9J inches long, of varied dark colora- 
tion, with the crown glossy steel-blue, and the under parts 
from the neck white with a silky luster and dappled with 
dusky spots. An inexact synonym of this genus is Sylbeo- 
cyclus. 
tachycardia (tak-i-kar'di-a), . [NL., < Gr. 
Ta%vf, swift, + Kapdia, the heart.] \npathol., 
excessive frequency of the pulse. 
tachydidaxy (tak'i-di-dak"si), w. [< Gr. raxi'S, 
swift, -I- SiSa^if, teaching, < SiSaan.cn', teach: 
see didactic.] A method of imparting know- 
ledge rapidly. [Rare.] Imp. lUct. 
tachydrome'(tak'i-dr6m), n. A bird of the ge- 
nus Cursoriii.i. 
Tachyglossa (tak-i-glos'ii), .pl [NL., < Gr. 
TO^I'T, swift, + }'/.uaaa, tongue.] The family 
