Английский Этимологический словарь - set (v.)

- O.E. settan "cause to sit, put in some place, fix firmly," causative form of sittan "to sit," from P.Gmc. *satjanan. Meaning "group of pieces musicians perform at a club during 45 minutes (more or less) is from c.1925, though it is found in a similar sense in 1590. Meaning "ready, prepared" first recorded 1844. Confused with sit since early 14c. Set-to "bout, fight" is 1743, originally pugilistic slang. Setup "arrangement" is from 1890. To set (someone) back "cost" is from 1900.