The username and password for logging in to a computer account. / An attempt to log in. / (more generally) An instance of signing on to something. / A person who signs on to something.

plural of at-sign

(broadcasting) The time of day when a radio or television station begins broadcasting, usually after being off the air for several hours. / Alternative form of sign-on

Alternative form of at sign

(computing) The convention by which one bit in the representation of a number indicates the numeric sign, while the rest indicate the magnitude.

simple past tense and past participle of sign up

simple past tense and past participle of sign out

(of an autograph) Having the signature alone, rather than being accompanied by other words or drawings.

simple past tense and past participle of co-sign

simple past tense and past participle of sign off