I. (ˈ) ̷ ̷| ̷ ̷ adverb
Etymology: erst + while
: in the past : formerly:
a. : in a time past : of old : once
found an apartment house where erstwhile stood his childhood home
: a short while since : of late : but now
the school-bound child who it seems erstwhile wailed in your arms
b. : till then or now : previously , heretofore
the new cheerfulness of the erstwhile unhappy man
II. ˈ ̷ ̷ˌ ̷ ̷ adjective
1. : having been or existed at some past time : of the past : onetime , sometime , former
the new manager was an erstwhile machinist who had risen to the top
deserted their erstwhile friends and allies
2. : being, existing, or effective till then or now : previous
invading the erstwhile domain of the specialists