I thought of this one when I was writing up my post on some time, sometime or sometimes. The word erstwhile popped into my head, and I thought that I’d better check if it officially meant something different from sometime.
Erstwhile means former as an adjective and formerly as an adverb: “Her erstwhile lover was now a senior politician”.
Sometime as an adjective means former; as an adverb it means at some unknown/unspecified time, with formerly marked as an archaic use in most dictionaries that I checked. In American English, it is also used for occasional.
I like erstwhile. It’s a nice, odd word that’s a bit hard to type. Let’s try to keep it going, even if it does essentially mean the same as sometime!
You can find more troublesome pairs here and the index to them all so far is here.
LibroEditing proofreading, editing, transcription, localisation 
Nordie
July 22, 2013 at 8:33 am
Hmmm, ok Never thought of Erstwhile as meaning “former” – not actually sure what i thought it meant – perhaps “steady”?!
Anyway, will be interesting to see what other people think of this
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Liz at Libro
July 22, 2013 at 8:34 am
Interesting, I do like hearing what people thought things meant!
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Mary Moss
August 7, 2013 at 8:40 pm
Interesting. I have always used “erstwhile” interchangeably with “sometime” in the American sense of “occasional” as well as in the sense of “former.” It appears that I have used “erstwhile” incorrectly in the former sense and should only be using it in the latter sense, that is to say “former.” My what a tangle the preceding sentence was. Or could I say erstwhile sentence 😉
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Liz at Libro
August 8, 2013 at 8:07 pm
Well you’re using the word and that’s something – I don’t like to see these interesting ones dying out! And now you know the fine detail, too!
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Victor Baird
June 17, 2014 at 10:21 pm
I used the term for my IBP (Independent Book Publishing Co.). I write about bygone railroads and think it is appropriate. I have also received favorable comments about the name too. The E-R-S-T in Erstwhile also stands for “Every Railroad has a Story to Tell” (Trademarked). .
IThe first book came out in December 2013 and half the books are gone now ( June 2014)and that was without dealing with the big wholesalers like Amazon. Admittedly, I started by writing magazine articles about trains years ago, plus do presentations. This helped me develop contacts and customers.
Victor Baird at Erstwhile Publications
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Liz at Libro
June 18, 2014 at 9:56 am
Thanks for your comment, Victor, and I hope your publishing company continues to go from strength to strength. Nice to see the word being used!
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