erstwhile

erst (“first, formerly”) +‎ while

• (UK) IPA^(key): /ˈɜː(ɹ)st.waɪl/
• (US) IPA^(key): /ˈɚst.waɪl/

erstwhile (not comparable)

1. Formerly; in the past.

• erewhile

erstwhile (not comparable)

1. (literary, law) Former, previous.

   Synonyms: former, once, previous, quondam, onetime; see also Thesaurus:former

   • 1905, Baroness Emmuska Orczy, chapter 2, in The Disappearance of Count Collini‎:

     “Scarcely had Alice reached her twentieth birthday, than she gave her erstwhile fiancée [sic] his formal congé. […]”

   • 2017 October 14, Paul Doyle, “Mauricio Pellegrino yet to find attacking solution for stuttering Southampton”, in the Guardian‎:

     Other erstwhile stalwarts are also wavering. Southampton had two of the best full-backs in the league last season but Ryan Bertrand has been below par this season and Cédric Soares made an uncharacteristic lapse that led to Stoke’s winning goal in Southampton’s last outing.

2. (proscribed) Respected, honourable.
   • 1999 November 1, Frank Bruni, quoting George W. Bush, “For Bush, an Adjustable Speech Of Tested Themes and Phrases”, in New York Times‎:

     If you're for one of my erstwhile opponents, that's O.K. Just don't work too hard.

The use of erstwhile to mean “respected” stems from a conflation with esteemed in phrases such as erstwhile colleague, and is proscribed by most authorities.[1][2]

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