chief digestive enzyme of pancreatic juice, 1876, coined 1874 by German physiologist Wilhelm Friedrich Kühne (1837-1900), apparently from Greek tripsis "rubbing, friction" (from tribein "to rub, rub down, wear away," from PIE root *tere- (1) "to rub, turn") + chemical suffix -in (2). Said to be so called because it first was obtained (in 1862) by rubbing the pancreas with glycerin.
-ic
Middle English -ik, -ick, word-forming element making adjectives, "having to do with, having the nature of, being, made of, caused by, similar to," from French -ique and directly from Latin -icus or from cognate Greek -ikos "in the manner of; pertaining to." From PIE adjective suffix *-(i)ko, which also yielded Slavic -isku, adjectival suffix indicating origin, the source of the -sky (Russian -skii) in many surnames. In chemistry, indicating a higher valence than names in -ous (first in benzoic, 1791).
In Middle English and after often spelled -ick, -ike, -ique. Variant forms in -ick (critick, ethick) were common in early Modern English and survived in English dictionaries into early 19c. This spelling was supported by Johnson but opposed by Webster, who prevailed.
tryptophan n.
also tryptophane, complex amino acid, 1890, coined in German (1876) from trypto-, taken as a combining form of tryptic "by trypsin" (see trypsin) + Greek phainein "bring to light, cause to appear, show" (from PIE root *bha- (1) "to shine").