Discussion Forum—A Way with Words, a fun radio show and podcast about language

Today, I heard a radio interview in which the subject used the adverb impromptly to mean "in an impromptu way." It got me thinking and looking things up. It seems that OFFICIALLY, impromptu is both the adjective form AND the adverb — and, of course, a noun for a kind of a musical composition.

Unofficially, I almost never see impromptu in an adverbial use. (e.g. We met impromptu on the morale issue.) When people intend an adverbial form of impromptu I do see mostly impromptly and impromptuly some. (e.g. We met impromptly on the morale issue. We met impromptuly on the morale issue.) What is especially interesting to me is that I also see the word imprompt used as an adjective in a context that means "impromptu," presumably as a back-formation from impromptly. (e.g. We had an imprompt meeting on the morale issue.)

Note: While imprompt appears in some references as an adjective, the meaning has more to do with the negation of prompt (adj.) and is glossed as "not ready."

What are your thoughts?