sign in

present singular third person signs in · participle present signing in · participle past signed in · past signed in

1. idiomaticTo sign one's name on a list when entering a place, to indicate one's arrival.

   In order to get into the office after hours, you'll have to sign in at the security desk.

   1 more example

   Harper signed in with the rangemaster and handed him her gun. He reloaded it with six shells and handed it back, together with two sets of ear defenders.

   2007, Lee Child, Running Blind: A Jack Reacher Novel

2. computingTo take some action to access a secured program or web page on a computer; to log in.

   He signed in using his own cybername: Point Guard.

   1999, Jacqueline Guest, Triple Threat