A term is like a semester, but shorter. Some people say "trimester" or "quarter", but "term" sounds more like Harry Potter.
Knox has three major terms: Fall term, Winter term, and Spring term. There is also December term, but it's shorter than the other three and most people don't take classes during it.
Rep term sounds like a fifth term, but it's not. It actually happens during Winter term, but only every three years.