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general::
Phrase(s): talk shop
to talk about business or work matters at a social event (where such talk is out of place). • All right, everyone, we’re not here to talk shop. Let’s have a good time. • Mary and Jane stood by the punch bowl, talking shop.
McGrawhill's American Idioms And Phrasal Verbs
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Converse about one's business or profession, as in Whenever John and his dad get together, they talk shop. [Mid-1800s]
American Heritage Idioms