Hi Matilda,Originally Posted by matilda
The phrase is normally associated with the related idiom "social circuit". A circuit in this context is a group of events or gatherings closely tied by common purpose and/or common participants. You might have a number of friends with whom you share regular weekend meetings. This collection of friends and their regular meetings would form your "social circuit". When you "hit the circuit", you are saying that you are joining in with the collective round of activities.
For example, "I've been busy studying for a few weeks, but tonight I'm going to 'hit the circuit' and enjoy myself."