Erstwhile and Prior to

Erstwhile

Erstwhile adverb - At an earlier or previous time.

Prior to and erstwhile are semantically related. In some cases you can use "Prior to" instead an adverb "Erstwhile".

Prior to

Prior to preposition - Earlier than.

Erstwhile and prior to are semantically related. Sometimes you can use "Erstwhile" instead an adverb phrase "Prior to".
Cite this Source
Prior to and Erstwhile. (2016). Retrieved 2026, August 13, from https://thesaurus.plus/related/erstwhile/prior_to
Erstwhile & Prior to. N.p., 2016. Web. 13 Aug. 2026. <https://thesaurus.plus/related/erstwhile/prior_to>.
Prior to or Erstwhile. 2016. Accessed August 13, 2026. https://thesaurus.plus/related/erstwhile/prior_to.
Google Ngram Viewer shows how "erstwhile" and "prior to" have occurred on timeline