1) Aimless bit of gunfire 2) Careless criticism 3) Casual criticism 4) Cheap insult 5) Haphazard try 6) Incidental criticism 7) Matter of chance 8) Offhand barb 9) Random attack 10) Random criticism 11) Saucepan ammunition 12) Shooting 13) Shot 14) Sniping remark 15) Wild criticism 1) Barb 
[n] - criticism aimed at an easy target and made without careful consideration 2. [n] - a shot taken at an easy or casual target (as by a pothunter)
noun a shot taken at an easy or casual target (as by a pothunter)