sign up
phrasal verbsign on/up | sign somebody on/up
- to sign a form or contract which says that you agree to do a job or become a soldier; to persuade somebody to sign a form or contract like this synonym enlist
- He signed on for five years in the army.
- The company has signed up three top models for the fashion show.
sign up (for something)
- to arrange to do a course of study by adding your name to the list of people doing it
- You can sign up online for language classes.