[yes.ter.day] adv [ME yisterday, fr. OE giestran daeg, fr. giestran yesterday + daeg day; akin to OHG gestaron yesterday, L heri, Gk chthes] (bef. 12c) 1: on the day last past: on the day preceding today
2: at a time not long past: only a short time ago "I wasn't born ~" -- yesterday adj
[2]yesterday n (bef. 12c) 1: the day last past: the day next before the present
2: recent time: time not long past
3: past time--usu. used in pl.