sign on

verb

signed on; signing on; signs on

intransitive verb

1

: to engage oneself by or as if by a signature

signed on to the new project

2

: to announce the start of broadcasting for the day

sign-on

ˈsī-ˌnȯn 

-ˌnän

noun

Synonyms of sign on

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

Examples of sign on in a Sentence

I signed on for the crew team simply as a lark

Recent Examples on the Web

More than 220 state governors, utilities, electric cooperatives, data center operators and other entities have signed on, according to the White House. — Kristi Swartz, AJC.com, 24 July 2026

With Saudi Arabia signed on to host the 2034 World Cup, FIFA will have to trot out a reprise of the November-December schedule that was necessitated by holding the 2022 tourney in Qatar. — Anthony Crupi, Sportico.com, 24 July 2026

The Memorandum of Understanding signed on June 17 asserts that Iran can never develop a nuclear weapon—a promise the regime has made in the past. — Callum Sutherland, Time, 24 July 2026

However, the convention’s effectiveness is severely hindered when many of the world’s largest, wealthiest and most influential countries have not signed on to it. — Nathan W. Cooper, The Conversation, 23 July 2026

Word History

First Known Use

1879, in the meaning defined at sense 1

Rhymes for sign on

• anton
• argon
• axon
• baronne
• baryon
• baton
• boron
• buisson
• bygone
• capon
• cardon
• chiffon

Kids Definition

sign on

verb

(ˈ)sī-ˈnȯn, 

-ˈnän

1

: to hire oneself by or as if by a signature

signed on as a member of the crew

2

: to announce the beginning of broadcasting