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ad. In the past; at a former time; formerly.

adj. Former: our erstwhile companions.

ad. Formerly; in the past.

adj. Former, previous.

ad. Till then or now; heretofore; formerly.

At one time; formerly.

adj. belonging to some prior time

ad. at a previous time

"Quickly she called her erstwhile boyfriend Danny and warned him that the guy he found suspicious was now at another casino."

past   

heretofore    formerly    erewhile    former    previous    once    quondam   

longtime    one-time    would-be    sometime    onetime    rightful    illustrious    hapless    self-appointed    quondam