self-

Old English self, sylf (West Saxon),  seolf (Anglian), "one's own person, -self; own, personal; same, identical," from Proto-Germanic *selbaz (source also of Old Norse sjalfr, Old Frisian self, Dutch zelf, Old High German selb, German selb, selbst, Gothic silba), Proto-Germanic *selbaz "self," from PIE *sel-bho-, suffixed form of root *s(w)e-, pronoun of the third person and reflexive (referring back to the subject of a sentence), also used in forms denoting the speaker's social group, "(we our-)selves" (see idiom).

Its use as the second element in compounded reflexive pronouns (herself, etc.) was in Old English, from the original independent (and inflected) use of self following personal pronouns, as in ic selfa "myself," min selfes "of myself." With a merging of accusative, dative, and genitive cases.

As a noun from c. 1200 as "the person or thing previously specified;" early 14c. as "a person in relation to that same person." G.M. Hopkins used selve as a verb, "become or cause to become a unique self" (1880) but its use seems to have been restricted to poets.

word-forming element meaning "self, one's own, by oneself, of oneself" (and especially, from 1895, "automobile"), from Greek autos, reflexive pronoun, "self, same," which is of unknown origin. It also was a common word-forming element in ancient Greek, as in modern English, but very few of the old words have survived the interval. In Greek, as a word-forming element, auto- had the sense of "self, one's own, of oneself ('independently'); of itself ('natural, native, not made'); just exactly; together with." Before a vowel, it became aut-; before an aspirate, auth-. In Greek it also was used as a prefix to proper names, as in automelinna "Melinna herself." The opposite prefix would be allo-.