taurine (n.)

zodiac constellation, late Old English, from Latin taurus "bull, bullock, steer," also the name of the constellation, from PIE *tau-ro- "bull" (source also of Greek tauros, Old Church Slavonic turu "bull, steer;" Lithuanian tauras "aurochs;" Old Prussian tauris "bison"); from PIE *tauro- "bull," from root *(s)taeu- "stout, standing, strong" (source also of Sanskrit sthura- "thick, compact," Avestan staora- "big cattle," Middle Persian stor "horse, draft animal," Gothic stiur "young bull," Old English steor); extended form of root *sta- "to stand, make or be firm."

Klein proposes a Semitic origin (compare Aramaic tora "ox, bull, steer," Hebrew shor, Arabic thor, Ethiopian sor). De Vaan writes: "The earlier history of the word is uncertain: there is no cognate in [Indo-Iranian] or Tocharian, whereas there are Semitic words for 'bull' which are conspicuously similar. Hence, it may have been an early loanword of the form *tauro- into the western IE languages." Meaning "person born under the sign of the bull" is recorded from 1901. The Taurid meteors (peaking Nov. 20) so called from 1878.

At midnight revels when the gossips met,

He was the theme of their eternal chat:

This ask'd what form great Jove would next devise,

And when his godship would again Taurise?

[William Somerville, "The Wife," 1727]

also -in, adjectival word-forming element, Middle English, from Old French -in/-ine, or directly from Latin suffix -inus/-ina/-inum "of, like," forming adjectives and derived nouns, as in divinus, feminus, caninus; from PIE adjectival suffix *-no- (see -en (2)).

The Latin suffix is cognate with Greek -inos/-ine/-inon, and in some modern scientific words the element is from Greek. Added to names, it meant "of or pertaining to, of the nature of" (Florentinus), and so it also was commonly used in forming Roman proper names, originally appellatives (Augustinus, Constantinus, Justinus, etc.) and its descendants in Romanic languages continued active in name-forming. The Latin fem. form, -ina, was used in forming abstracts (doctrina, medicina). Relics of the attempt to continue a distinction between Latin -ina and -inus account for the English hesitation in spelling between -in and -ine.

word-forming element in chemistry, often interchangeable with -in (2), though modern use distinguishes them; early 19c., from French -ine, the suffix commonly used to form words for derived substances, hence its extended use in chemistry. It was applied unsystematically at first (as in aniline), but now has more restricted use.

The French suffix is from Latin -ina, fem. form of -inus, suffix used to form adjectives from nouns, and thus is identical with -ine (1).