1. to watch, track or monitor closely
keep a tab on their work
When you 'keep a tab' or 'keep tabs' on something or somebody, you keep track of it or them and monitor it or them closely. This phrase can have a negative connotation, as it can portray surveillance or mistrust. Do not confuse with the phrase 'keep/run/have a tab' which means to run a bill in a bar or shop to be paid at a later time or date.