I was reading [the etymology](http://www.etymonline.com/index.php?term=inoculate&allowed_in_frame=0) of the Latinate English verb 'inoculate', the following from which generated the question entitled above: > [...] *inoculare* "graft in, implant a bud or **eye** of one plant into another," from in- "in" (see in- (2)) + oculus "bud," originally "**eye**" (see [eye](http://www.etymonline.com/index.php?term=eye&allowed_in_frame=0) (n.)).