c.1200, "animal hide" (usually dressed and tanned), from Old Norse skinn "animal hide, fur," from Proto-Germanic *skintha- (cf. Old English scinn (rare), Old High German scinten, German schinden "to flay, skin;" German dialectal schind "skin of a fruit," Flemish schinde "bark"), from PIE *sken- "to cut off" (cf. Breton scant "scale of a fish," Irish scainim "I tear, I burst"), from root *sek- "to cut" (see section (n.)).
The usual Anglo-Saxon word is hide (n.1). Meaning "epidermis of a living animal or person" is attested from early 14c.; extended to fruits, vegetables, etc. late 14c. Jazz slang sense of "drum" is from 1927. Meaning "a skinhead" is from 1970. As an adjective, it formerly had a slang sense of "cheating" (1868); sense of "pornographic" is attested from 1968. Skin deep is first attested in this:
The skin of one's teeth as the narrowest of margins is attested from 1550s in the Geneva Bible literal translation of the Hebrew text in Job xix:20. To get under (someone's) skin "annoy" is from 1896. Skin-graft is from 1871. Skin merchant "recruiting officer" is from 1792.