Familiarity or acquaintance with something; the state of being conversant or knowledgeable about a subject.
From conversant + -ance (suffix forming nouns from adjectives, from Latin -antia). The word developed in the 17th century to describe the quality of being familiar with or informed about something.
In legal and academic contexts, 'conversance' is still used—a lawyer might claim 'conversance with contract law.' It's a formal way of saying 'I know this subject well.' It's job-interview language: proof of expertise through a single word.
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