Of, relating to, or having the nature or style of a dissertation; prone to discoursing at length.
From 'dissertation' (or directly from Latin dissertare) plus the adjectival suffix -ive, meaning 'tending toward' or 'of the nature of.'
A 'dissertative' person is someone who can't just answer a simple question—they launch into a thorough, multi-part explanation with footnotes and citations, scholarly by temperament.
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