treat [ME] Treat is first recorded with the meanings ‘negotiate’ and ‘discuss (a subject)’. It is from Old French traitier, from Latin tractare ‘handle’. The sense ‘event that gives great pleasure’ dates from the mid 17th century, developing via the senses ‘treatment of guests’ and the entertainment you put on for them. Late Middle English treatise is also from Old French traitier, while treaty [LME], and tract [LME] are related.