I. intransitive verb
: to engage oneself for duty by signature or agreement : enlist
signed on as a member of the crew
signed on for another six years
transitive verb
: to secure the signature of : sign up : employ
II. intransitive verb
( -s )
: to announce the start of broadcasting for the day
• sign-on ˈ ̷ ̷ ˌ ̷ ̷ noun