Idioms. You gotta love ‘em. This one has a particularly interesting history.
The word starkers showed up in English in 1923, meaning completely naked. Its roots appear in the term stark naked, which English speakers were using as early as 1520. At this point in the family roots, there’s an unexpected fork.
One would expect stark naked & starkers’ origins to be stark, which came from the Old English word stearc, which meant obstinate, severe, rigid, stiff, stern, strong or violent. By the 1400s, the idiom stark dead came about. Though stark actually referred to the rigidity of a corpse, popular understanding led to the belief that stark was intensifying dead, much like saying truly dead or very dead. It appears this caused the meaning of stark to shift to mean utter, sheer or complete. By the 1640s, that newly established meaning contributed to the Idiom stark raving, possibly translatable today as totally psycho. By the 1830s, stark added a new meaning, bare or barren.
Some other words that were born into Old English of the stiff meaning of stearc include stork, thorn (who would’ve thunk?) & possibly stretch. A century or more later, starch, stereo, & sterile all came from the stiff or rigid meaning of stark.
But wait. What about that previously mentioned “unexpected fork” in the family roots? The two words or terms above that didn’t come from stearc are stark naked & starkers. They came from another Old English word, steort, which is also the root of the name of a bird called a redstart, a colorful critter named for its red derriere. All this because steort meant rear end, rump or buttocks, which leads to the realization that stark naked actually translates to mean butt naked.
Idioms. You gotta love ‘em.