incidence 
a perpendicular CD be erected, then the angle BCD is 
generally called the angle of incidence. Some authors 
make ACE the angle of incidence. 
Those bodies which give light by reflexion, can there 
only be perceived where the angle of reflexion is equal to 
the angle uf incidence. 
Bp. Wilson, Discovery of a New World. 
(6) In j>. , the angle which the longer axis of a projectile 
makes with the surface struck. Axis Of incidence, the 
normal to a surface at the point at which a ray or body 
strikes upon it. CathetUS of incidence. Same as axis 
of incitience. Incidence formula, in enumeratioegeom., 
a formula expressing the number of incidences between 
different figures. For example, one such formula expresses 
the following proposition : In any uuidimensional system 
of curves the number of them which cut a given straight 
line added to the number which touch a given plane give 
the number which so cut a plane that the tangent at the 
point of intersection cuts agiven straight line. Plane of 
incidence, the plane passing through the incident ray (EC) 
and the normal to the surface (CD). See figure above. 
incidencyt (in'si-den-si), n. Same as incidence, 1. 
But wise men, philosophers and private judges, take in 
the accounts of accidental moments tu\&incidencies to the 
action, said Cicero. Jer. Taylor, Of Repentance, ill 3. 
incident (in'si-deut), a. and n. [< F. incident 
= Sp. Pg. It. incidents, < L. inciden(t-)s, ppr. 
of incidere. fall upon, < in, on, + cadere, fall : 
Beecadent.] I. a. 1. Falling or striking upon 
something, as a ray of light or a projectile ; im- 
pinging or acting upon anything from without. 
That there may be continuous changes of structure in 
organisms, there must be continuous changes in the inci- 
dent forces. H. Spencer, Priu. of Biol., f 169. 
If light be incident at the polarizing angle, the reflected 
and refracted rays will be at right angles to one another. 
Spottiswoode, Polarisation, p. 9. 
2. Likely to happen ; apt to occur ; hence, natu- 
rally appertaining; necessarily conjoined. 
I have been looking at the fire, and in a pensive man- 
ner reflecting upon the great misfortunes and calamities 
incident to human life. Steele, Tatler, No. 82. 
Truly and heartily will he know where to find a true 
and sweet mate, without any risk such as Hilton deplores 
as incident to scholars and great men. Emerson, Love. 
3. Appertaining to or following another thing; 
conjoined as a subordinate to a principal thing; 
appurtenant : as, 1'ent is incident to a reversion. 
To whom it was incident as a fee of his office. 
Puttenham, Arte of Eng. Poesie, p. 238. 
4f. Subordinate; casual; incidental. 
Men's rarer incident necessities and utilities. 
Hooker, Eccles. Polity. 
Incident proposition, in logic, a subordinate proposi- 
tion or clause inserted in a principal proposition, and 
called determinative or explicative according as it forms 
an essential or only an accessory member of it: as, Na- 
?les, where I met my friends, is a beautiful city. =Syn. 
ncident, Liable. "Incident is improperly confounded 
with liable. Says a living writer, 'The work was incident 
to decay.' He should have turned it end for end. Decay 
may be incident to a work ; the work is liable to decay." 
A. Phelps, Eng. Style, p. 371. 
The regular jealous-fit that's incident 
To all old husbands that wed brisk young wives. 
Browning, Ring and Book, I. 76. 
Proudly secure, yet liable to fall. Milton, S. A., 1. 65. 
II. n. 1. That which falls out or takes place; 
an occurrence; something which takes place 
in connection with an event or a series of events 
of greater importance. 
A writer of lives may descend, with propriety, to minute 
circumstances and familiar incidents. 
H. Blair, Rhetoric, xxxvi. 
The incident had occurred and was gone for me ; it was 
an incident of no moment, no romance, no interest in a 
sense ; yet it marked with change one single hour of a 
monotonous life. Charlotte Bronte, Jane Eyre, xii. 
2. A thing necessarily or frequently depending 
upon, appertaining to, or legally passing with 
another that is the principal or more impor- 
tant; a natural or characteristic accompani- 
ment. 
Representative Councils, &c., are a mere incident and 
not an essential to Corporations. The whole body is the 
Corporation. 
Quoted in English Gilds (E. E. T. 8.), Int., p. xxii. 
To every estate in lands the law has annexed certain 
peculiar incidents which appertain to it as of course with- 
out being expressly enumerated. Burrill. 
3. In decorative art, the representation of any 
action, often much conventionalized, but still 
to be recognized: thus, a frieze may consist of 
a number of incidents relating collectively some 
historical event. =Syn. 1. Occurrence, Circumstance, 
etc. See eventi. 
incidental (iu-si-den'tal), a. and n. [< incident 
I- -al.] I. a. Occurring, inseparably or fortu- 
itously, in conjunction with something else, 
usually of greater importance; of minor im- 
portance ; occasional ; casual : as incidental ex- 
penses. 
The pleasure incidental to the satisfaction of an inter- 
est cannot be attained after loss of the interest itself. 
T. H. Green, Prolegomena to Ethics, 161. 
3036 
It would be very useful indeed to have a record of the 
incidental discoveries, and of the minor studies which 
every historical scholar makes in the process of his work. 
Stubbs, Medieval and Modern Hist., p. 54. 
Poverty has one incidental advantage ; it lets things fall 
to ruin, but it does not improve or restore. 
E. A. Freeman, Venice, p. 215. 
In England inequality lies imbedded in the very base 
of the social structure ; in America it is a late, incidental, 
unrecognized product. Gladstone, Might of Right, p. 179. 
= Syn. Chance, Casual, et. See accidental. 
II. n. Something subordinate or casual: of- 
ten used in the plural to mean minor expenses. 
So many weak, pitiful incidentals attend on them. Pope. 
Your father said that I might pay you five francs a day 
for incidentals and pocket money. 
Jacub Abbott, Hollo in Paris, i. 
incidentally (in-si-den'tal-i), adv. In an in- 
cidental manner ; as an incident ; casually. 
I ... treat either purposely or incidentally of ... 
colours. Boyle, Works, I. 665. 
incidentaryt, a. [< incident + -ary.] Inci- 
dental. 
He had been near fifty years from the county of Car- 
narvon and the town of Conway, unless by incidentary 
visits. Bp. Hacket, Abp. Williams, ii. 208. 
incidentless (in'si-dent-les), a. [< incident + 
-less.] Without incident ; uneventful. 
My journey was incidentlesn, but the moment I came 
into Brighthelmstone I was met by Mrs. Thrale. 
Mme. D'Arblay, Diary, II. 158. 
incidentlyt (in'si-dent-li), adv. Incidentally. 
It was incidently moved amongst the j ndges what should 
be done for the king himself, who was attainted. 
Bacon, Hist Hen. VII. 
incindermentt (in-sin'der-ment), n. [< in- 2 + 
cinder + -ment. Cf. incinerate.] Incineration. 
Hee, like the glorious rare Arabian bird, 
Will soon result from His incinderment. 
Dames, Holy Roode, p. 26. 
incinerable (in-sin'e-ra-bl), a. [< ML. as if *in- 
cinerabilis, < incinerare, burn to ashes: see in- 
cinerate.] Capable of being reduced to ashes: 
as, incinerable matter. [Rare.] 
Other incinerable substances were found so fresh that 
they could feel no sindge from fire. 
Sir T. Browne, Urn-burial, UL 
incinerate (in-sin'e-rat), v. t.; pret. and pp. 
incinerated, ppr. incinerating. [Formerly also 
eiicinerate; \ ML. incineratus, pp. of incinerare 
(> It. incenerare = Sp. Pg. Pr. incinerar = F. 
incinerer), burn to ashes, < L. in, in, to, + einis 
(ciner-), ashes : see cinerary.] To burn to ashes. 
Near the same plot of ground, for about six yards com- 
passe, were digged up coals and incinerated substances. 
Sir T. Browne, Urn-burial, ii. 
incineratet (in-sin'e-rat), a. [< ML. incinera- 
tus, pp. : see the verb.] Burnt to ashes. 
Fire burneth wood, making it first luminous, then black 
and brittle, and lastly broken and incinerate. Bacon. 
incineration (in-siu-e-ra'shon), . [= F. in- 
cineration = Pr. incineratio = Sp. incineracion 
|= Pg. incineracSo = It. incenerazione, < ML. 
\jincineratio(n-), < incinerare, burn to ashes : see 
incinerate.] The act of incinerating or redu- 
cing to ashes by combustion. 
Tobacco stalks may be mentioned as yielding upon incin- 
eration large quantities of potassium salts. 
Spans' Encyc. Manvf.,1. 255. 
incinerator (in-sin'e-ra-tor), 7i. [< ML. as if 
"incinerator. < incinerare, incinerate: see incin- 
erate.] A furnace or retort for consuming, or 
reducing to ashes, any substance or body. 
The incinerator (Dr. Sargeant's Patent), for destroying 
the refuse of hospitals, asylums, workhouses, etc. 
The Engineer, LXVII., p. xxvii. of adv'ts. 
incipience, incipiency (in-sip'i-ens, -en-si), n. 
[< incipient.] The condition of being incipient ; 
beginning ; commencement, 
incipient (in-sip'i-ent), o. [= Sp. Pg. It. incipi- 
ente, < L. incipien(i-)s, ppr. of incipere, begin, lit. 
take up, < in, on, + capere, take : see capable. 
Cf. incept.] Beginning; commencing; entering 
on existence or appearance. 
He dashed my incipient vanity to the earth at once. 
Lamb, Old and New Schoolmaster. 
Its blasting rebuke causes incipient despotism to perish 
in the bud. D. Webster, Speech, Oct. 12, 1832. 
Incipient cause, a cause which extrinsically excites the 
principal cause to action; a procatarctic or inchoating 
cause. 
incipiently (in-sip'i-ent-li), adv. In an incipi- 
ent manner, 
in-circle (in'ser-kl), w. [< jl + circle.] An 
inscribed circle. 
incircle (in-ser'kl), v. t. [< in-2 + circle.] Same 
as encircle. 
incirclett (in-ser'klet), . Same as encirclet. 
incircumscriptible (in-ser-kum-skrip'ti-bl), a. 
[= F. incirconscriptible = It. incircoscrittibile ; 
Incision 
as in- 3 + circumscriptible.] Incapable of being 
circumscribed or limited ; illimitable. 
The glorious bodie of Christ, which should bee capable 
of ten thousand places at once, both in heaven and earth, 
invisible, incircumscriptible. 
Bp. Hall, The Old Religion, f 2. 
incircumscription (in-ser-kum-skrip'shon), n. 
[X i- 3 + circumscription.] The condition or 
quality of being incircumscriptible or limit- 
less. 
His mercy hath all its operations upon man, and returns 
to its own centre, and incircumscription, and infinity, un- 
less it issues forth upon us. 
Jer. Taylor, Works (ed. 1835X I. 914. 
incircumspect (in-ser'kum-spekt), a. [= F. 
incirconspect = It. incircospetto ; as in- 3 + cir- 
cumspect."] Not circumspect ; heedless. 
Our fashions of eating make us ... unlusty to labour, 
. . . incircumspect, inconsiderate, heady, rash. 
Tyndale, Works, p. 227. 
incircumspection (in-ser-kum-spek'shon), n. 
[= F. incirconspection; as in- 3 + circumspec- 
tion.'] Want of circumspection ; heedlessness. 
An unexpected way of delusion, and whereby he more 
easily led away the incircumspection of their belief. 
Sir T. Browne, Vulg. Err., i. 11. 
incircumspectly (in-ser'kum-spekt-li), adv. 
Not circumspectly. 
The Christians, inuading and entring into the munition 
incircuiHxpectly, were pelted and pashed with stones. 
Hakluyt's Voyages, II. 36. 
incise (in-siz'), v. t. ; pret. and pp. incised, ppr. 
incising. |X F. inciser, < L. incisus, pp. of in- 
cidere, cut into: see incide.] To cut in or into; 
form or treat by cutting; specifically, to en- 
grave; carve in intaglio. 
I on this grave thy epitaph incise. 
Carew, Death of Dr. Donne. 
The hair is indicated by masses broadly modelled, with 
incised lines on the surface. 
A. S. Murray, Greek Sculpture, I. 110. 
Whereon a rude hand is incised a favorite Mohamme- 
dan symbol of doctrine. Lathrop, Spanish Vistas, p. 135. 
incised (iu-slzd'),j>. a. 1. Cut; caused by cut- 
ting: as, an incised wound. 2. In l>ot. and en- 
tom., appearing as if cut ; having marginal slits 
or notches, as an oak-leaf or an insect's wing. 
Incised enamel. Same as champleve enamel. See 
enamel. Incised ware. SeewareH. 
incisely (in-sls'li), adv. [< "incise, a., incised 
(< L. incisus, pp.: see incise, .), + -fy 2 .] With 
or by incisions or notches. Eaton. [Rare.] 
incisiform(in-si'si-form),o. [Short for "incisori- 
form, < NL. incisor, incisor, + L. forma, form.] 
mzodl. : (a) Resembling an incisor tooth; inci- 
sorial: as, "lower canines incisiform," Floicer. 
In the genus Dinoceras there are three incisor teeth, 
and a small incisiform canine on each side. 
Amer. Jour. Sci., 3d ser., XXIX. 187. 
(6) More particularly, having the form or char- 
acter of the incisor teeth of a rodent ; glirif orm, 
as teeth. See incisor. 
incision (in-sizh'on), n. [< F. incision = Pr. 
incizio = Sp. incision = Pg. incisao = It. tnct- 
sione, a cutting into, < L. incisio(n-), a cutting 
into, used only in fig. senses, division, cesura, 
< incidere, pp. incisus, cut into: see incide, in- 
cise.'] 1. The act of incising or cutting into a 
substance; specifically, the act of cutting into 
flesh, as for the purpose of bloodletting. 
A fever in your blood ! why, then incision 
Would let her out in saucers. 
Shak., L L. L., iv. 8. 
With nice indrion of her guided steel 
She [the chisel] ploughs a brazen field. 
Cowjter, Task, i. 708. 
When as Nature teaches us to divide any limb from the 
body to the saving of its fellows, . . . how much more is 
it her doctrine to sever by incision ... a sore, the gan- 
green of a limb, to the recovery of a whole man? 
Hilton, Tetrachordon. 
2. A division or passage made by cutting; a 
cut or cutting; a gash. 
Let us make indrion for your love, 
To prove whose blood is reddest. 
Shak., M. of V., 11. 1. 
3. Figuratively, trenchancy; incisiveness. 
[Rare.] 
The bards performed the function of public censors with 
sharp incision. J. S. Blackie. 
4. In hot. and entom., a slit or deep notch re- 
sembling a cut. 5. In Doric arch., same as hy- 
potrachelium. Sometimes, especially in provincial ex- 
amples, the incision is repeated to emphasize the separa- 
tion of the shaft and capital. See cut under hyputrache- 
lium. 
6f. A cutting away ; removal, as by an acid or 
a drug. 
Abstersion is a scouring off or incision of viscous hu- 
mours. Bacon. 
