Stark
Old English stearc ‘unyielding, severe’, of Germanic origin; related to Dutch sterk and German stark ‘strong’.
wiktionary
From Middle English stark, starc, from Old English stearc, starc(“stiff, rigid, unyielding, obstinate, hard, strong, severe, violent”), from Proto-West Germanic *stark, from Proto-Germanic *starkuz(“stiff, strong”), from Proto-Indo-European *(s)terg-(“rigid, stiff”). Cognate with Saterland Frisian sterc(“strong”), Dutch sterk(“strong”), Low German sterk(“strong”), German stark(“strong”), Danish stærk(“strong”), Swedish stark(“strong”), Norwegian sterk(“strong”), Icelandic sterkur(“strong”). Related to starch.
In the phrase stark naked: an alternation of start("tail" or "rump"), a literal parallel to the modern butt naked.
From Middle English starken, from Old English stearcian(“to stiffen, become hard, grow stiff or hard”), from Proto-Germanic *starkōną, *starkēną(“to stiffen, become hard”), from Proto-Indo-European *(s)terg-(“rigid, stiff”). Cognate with German erstarken(“to strengthen”).
etymonline
stark (adj.)
Old English stearc "stiff, strong, rigid, obstinate; stern, severe, hard; harsh, rough, violent," from Proto-Germanic *starka- (source also of Old Norse sterkr, Danish, Old Frisian sterk, Middle Dutch starc, Old High German starah, German stark, Gothic *starks), from PIE root *ster- (1) "stiff." From the same root as stern (adj.).
Meaning "utter, sheer, complete" first recorded c. 1400, perhaps from influence of common phrase stark dead (late 14c.), with stark mistaken as an intensive adjective. Sense of "bare, barren" is from 1833. As an adverb from c. 1200. Related: Starkly; starkness. Stark-raving (adj.) is from 1640s; earlier stark-staring 1530s.
