The meaning of Sign up

phrasal verb

Commit oneself to a period of employment, education, or in the armed forces.

Usage examples:

He was just seventeen when he signed up

phrasal verb

To join a group or organization

Usage examples:

Kathy signed up for the soccer team this year.

noun

An occasion when you start doing or having something or start being a member of a group, especially by signing a document

Usage examples:

Instead of paying a sign-up fee, investors pay a fee based on the amount they invest., the card rec…

phrasal verb

To agree to become involved in an organized activity

Usage examples:

[ + to infinitive ] i've signed up to make the sandwiches for the party., sign up for she's signed …