Familiar with or knowledgeable about something; having experience with or understanding of a subject.
From Latin conversari ('to live with' or 'to associate') + -ant suffix. The meaning shifted from 'associating with people' to 'familiar with ideas or subjects' by the 17th century.
To be 'conversant' with something means you know it well enough to discuss it intelligently—it's the professional equivalent of 'fluent.' Job postings demand candidates 'conversant with Python' or 'conversant with medieval history.' It's becoming the go-to word for expertise.
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