- A written work dealing formally and systematically with a subject: his treatise on Scottish political theoryMore example sentences
- They study magic and write treatises and quarrel, as scholars will, but none of them can cast a spell to save his life.
- He developed his interest in mechanics, writing treatises on his inventions which he circulated in manuscript.
- He wrote several intellectual treatises that are admired even today.
late Middle English: from Anglo-Norman French tretis, from Old French traitier (see treat).