intransitive verb

1. to discuss terms (with a person or for a settlement); negotiate
2. to deal with a subject in writing or speech; speak or write (of)
3. to stand the cost of another's or others' entertainment

Etymology: ME treten < OFr traiter, to handle, meddle, treat < L tractare, freq. of trahere, to draw

transitive verb

1. to deal with (a subject) in writing, speech, music, painting, etc., esp. in a specified manner or style
2. to act or behave toward (a person, animal, etc.) in a specified manner
3. to have a specified attitude toward and deal with accordingly to treat a mistake as a joke
4. 1. to pay for the food, drink, entertainment, etc. of (another or others)
   2. to provide with something that pleases
5. to subject to some process or to some substance in processing, as in a chemical procedure
6. to give medical or surgical care to (someone) or for (some disorder)

noun

1. a meal, drink, entertainment, etc. paid for by someone else
2. anything that gives great pleasure
3. 1. the act of treating or entertaining
   2. one's turn to treat