sign up

verb

signed up; signing up; signs up

intransitive verb

: to sign one's name (as to a contract) in order to obtain, do, or join something

sign up for insurance

sign up for classes

sign-up

ˈsī-ˌnəp 

noun or adjective

Synonyms of sign up

• join
• enter
• sign on (for)
• enlist (in)
• rejoin
• enroll (in)

Examples of sign up in a Sentence

they both signed up for a Spanish class

Recent Examples on the Web

Make sure to read through the list of coverages for your plan before signing up, and check the contract for stipulations and exclusions. —Dan Simms, USA Today, 23 Mar. 2026

Another option is to sign up for Clear, a program run by a private company that contracts with TSA and operates its own lines at the airport. —Mary Cunningham, CBS News, 23 Mar. 2026

Check out our Daily Deals for the best products at the best prices and sign up here to receive the BestReviews weekly newsletter full of shopping inspo and sales. —Bestreviews, Mercury News, 23 Mar. 2026

Read more of our stories about Philadelphia, or sign up for our Philadelphia newsletter on Substack. —Marla Miller, The Conversation, 23 Mar. 2026

Word History

First Known Use

1875, in the meaning defined above

Rhymes for sign up

• backup
• blowup
• breakup
• buildup
• checkup
• cleanup
• holdup
• hookup
• lineup
• lockup
• makeup
• markup

Kids Definition

sign up

verb

(ˈ)sī-ˈnəp

: to sign one's name in order to get, do, or take something

signed up for Spanish

sign-up noun or adjective