Erstwhile and Of old

Erstwhile adverb - At an earlier or previous time.

Of old and erstwhile are semantically related In some cases you can use "Of old" instead the word "Erstwhile" as an adjective or an adverb.

Erstwhile and of old are semantically related in old topic. Sometimes you can use "Erstwhile" instead the phrase "Of old" as an adjective or an adverb, if it concerns topics such as in the past, previously in time or order. obsolete substitute