\Trop"ic\, a. [Atropine + -ic.] (Chem.)
Of, pertaining to, or designating, an acid obtained from
atropine and certain other alkaloids, as a white crystalline
substance slightly soluble in water.

\Trop"ic\, n. [F. tropique, L. tropicus of or belonging
to a turn, i. e., of the sun, Gr. ? of the solstice, ? (sc.
?) the tropic or solstice, fr. ? to turn. See {Trope}.]
1. (Astron.) One of the two small circles of the celestial
   sphere, situated on each side of the equator, at a
   distance of 23[deg] 28[min], and parallel to it, which the
   sun just reaches at its greatest declination north or
   south, and from which it turns again toward the equator,
   the northern circle being called the {Tropic of Cancer},
   and the southern the {Tropic of Capricorn}, from the names
   of the two signs at which they touch the ecliptic.
2. (Geog.)
   (a) One of the two parallels of terrestrial latitude
       corresponding to the celestial tropics, and called by
       the same names.
   (b) pl. The region lying between these parallels of
       latitude, or near them on either side.
             The brilliant flowers of the tropics bloom from
             the windows of the greenhouse and the saloon.
                                               --Bancroft.

\Trop"ic\, a.
Of or pertaining to the tropics; tropical.
{Tropic bird} (Zo["o]l.), any one of three species of oceanic
   belonging to the genus {Pha["e]thon}, found chiefly in
   tropical seas. They are mostly white, and have two central
   tail feathers very long and slender. The yellow-billed
   tropic bird. {Pha["e]thon flavirostris} (called also
   {boatswain}), is found on the Atlantic coast of America,
   and is common at the Bermudas, where it breeds.