1650s in biology, "having or resembling a tendril;" 1815 in meteorology, from Latin cirrus "lock of hair, tendril" (see cirrus) + -ous. Also sometimes cirrose.

"a name rejected for linguistic reasons, bad nomenclature in botany or biology," 1888, from caco- "bad, ill, poor" + -onym "name" (from PIE root *no-men- "name").

"animal that preys upon another," 1862, from Latin praedator "plunderer," from praedari "to rob" (see predation). Latin Predatores (Swainson, 1840) was used in biology of the group of coleopterous insects that ate other insects.

1883, in biology, from French plasmolysis (1877), from plasmo- (see plasma) + Greek lysis "a loosening" (see -lysis). Related: Plasmolytic; plasmolyze.

"relating to or consisting of molecules," by 1815, from molecule + -ar or else from French moléculaire or Modern Latin molecularis. Molecular biology is attested by 1950.

"fish-shaped," 1870 in biology, 1879 in mythology, from ichthyo- "fish" + -morphic, from Greek morphē "form, shape," a word of uncertain etymology.

"most favorable," 1890, from optimum + -al (1), perhaps based on proximal, etc. Originally a word in biology. Related: Optimally; optimality.

word-forming element meaning, in meteorology, "involving cirrus clouds," and, in biology, "involving a tendril or tendrils," from combining form of Latin cirrus "lock of hair, tendril" (see cirrus).

1857 as a term in biology, "reproduce, grow by multiplication of elementary parts;" see proliferation. General sense, of things, etc., "increase greatly in numbers," by 1961. Related: Proliferated; proliferating.