g.try anything once: a cliché indicating (often somewhat unexpected) willingness on the part of a speaker to attempt or experience something new.
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the world > action or operation > endeavour > trial or experiment > try experiments or make experiment [verb (intransitive)] > be willing to try something new
try anything once1921
1921 Ladies' Home Jrnl. July 20/1 This slogan runs, ‘Try anything once’.
1959 N. MailerAdvts. for Myself (1961) 160 ‘I am sort of curious about the film. I've never seen one [sc. a pornographic film], you know.’ ‘Try anything once, is that it?’