3. Quickness of apprehension; readiness in learning; docility; as, an aptness to learn is more observable
in some children than in others.
4. Proneness; tendency; as, the aptness of iron to rust.
Aptote
(Ap"tote) n. [L. aptotum, Gr. indeclinable; 'a priv. + fallen, declined, to fall.] (Gram.) A noun
which has no distinction of cases; an indeclinable noun.
Aptotic
(Ap*tot"ic) a. Pertaining to, or characterized by, aptotes; uninflected; as, aptotic languages.
Aptychus
(||Ap"ty*chus) n. [NL., fr. Gr. 'a priv. + fold.] (Zoöl.) A shelly plate found in the terminal
chambers of ammonite shells. Some authors consider them to be jaws; others, opercula.
Apus
(||A"pus) n. [NL., fr. Gr. . See Apode, n.] (Zoöl.) A genus of fresh-water phyllopod crustaceans.
See Phyllopod.
Apyretic
(Ap`y*ret"ic) a. [Pref. a not + pyretic.] (Med.) Without fever; — applied to days when there
is an intermission of fever. Dunglison.
Apyrexia
(||Ap`y*rex"i*a Ap`y*rex`y) n. [NL. apyrexia, fr. Gr. 'a priv. + to be feverish, fr. fire: cf. F. apyrexie.]
(Med.) The absence or intermission of fever.
Apyrexial
(Ap`y*rex"i*al) a. (Med.) Relating to apyrexy. "Apyrexial period." Brande & C.
Apyrous
(Ap"y*rous) a. [Gr. 'a priv. + fire.] Incombustible; capable of sustaining a strong heat without
alteration of form or properties.
Aqua
(||A"qua) n. [L. See Ewer.] Water; — a word much used in pharmacy and the old chemistry, in
various signification, determined by the word or words annexed.
Aqua ammoniæ, the aqueous solution of ammonia; liquid ammonia; often called aqua ammonia. — Aqua
marine or Aqua marina Same as Aquamarine. — Aqua regia [L., royal water] (Chem.), a very
corrosive fuming yellow liquid consisting of nitric and hydrochloric acids. It has the power of dissolving
gold, the "royal" metal. — Aqua Tofana a fluid containing arsenic, and used for secret poisoning, made
by an Italian woman named Tofana, in the middle of the 17th century, who is said to have poisoned
more than 600 persons. Francis. — Aqua vitæ [L., water of life. Cf. Eau de vie, Usquebaugh], a
name given to brandy and some other ardent spirits. Shak.
Aqua fortis
(||A`qua for"tis) [L., strong water.] (Chem.) Nitric acid. [Archaic]
Aquamarine
(A`qua*ma*rine") n. (Min.) A transparent, pale green variety of beryl, used as a gem.
See Beryl.
Aquapuncture
(A`qua*punc"ture) n. [L. aqua water, + punctura puncture, pungere, punctum, to, prick.]
(Med.) The introduction of water subcutaneously for the relief of pain.
Aquarelle
(||Aq`ua*relle") n. [F., fr. Ital acquerello, fr. acqua water, L. aqua.] A design or painting in
thin transparent water colors; also, the mode of painting in such colors.
Aquarellist
(Aq`ua*rel"list) n. A painter in thin transparent water colors.
Aquarial
(A*qua"ri*al A*qua"ri*an) a. Of or pertaining to an aquarium.
Aquarian
(A*qua"ri*an), n. [L. (assumed) Aquarianus, fr. aqua: cf. F. Aquarien. See Aqua.] (Eccl.
Hist.) One of a sect of Christian in the primitive church who used water instead of wine in the Lord's
Supper.
