The word "محفل" (Mehfil) in Urdu refers to a social gathering or assembly, typically where people come together for various purposes, such as entertainment, discussion, music, poetry, or other forms of social interaction. A "Mehfil" can be a formal or informal gathering and is often associated with cultural and artistic events. In the context of the poem you provided, "محفل آذائی کا کب ہمیں ذوق تھا" implies that the speaker used to have an interest or taste for participating in or attending such gatherings where artistic or entertainment activities take place.
