base *sem- "one, together" (cf. Skt. samah "even, level, similar, identical;" Avestan hama "similar, the same;" Gk. hama "together with, at the same time," homos "one and the same," homios "like, resembling," homalos "even;" L. similis "like;" O.Ir. samail "likeness;" O.C.S. samu "himself"). O.E. had lost the pure form of the word; the modern word replaced synonymous
ilk (q.v.). Colloq. phrase same here as an exclamation of agreement is from 1895. Same difference curious way to say "equal," is attested from 1945.