time - the continuum of experience in which events pass from the future through the present to the past

bygone, water under the bridge - past events to be put aside; "let bygones be bygones"

old - past times (especially in the phrase `in days of old')

history - the aggregate of past events; "a critical time in the school's history"

time immemorial, time out of mind - the distant past beyond memory

auld langsyne, langsyne, old times, the good old days - past times remembered with nostalgia

yesterday - the recent past; "yesterday's solutions are not good enough"; "we shared many yesterdays"