What's the difference between i.e. and e.g.?
"having characteristics in common," 1610s (earlier similary, 1560s), from French similaire, from a Medieval Latin extended form of Latin similis "like, resembling," from Old Latin semol "together," from PIE root *sem- (1) "one, as one, together with" (see same). The noun meaning "that which is similar" is from 1650s. Related: Similarly.