Someone doing something that they shouldn't be doing e.g. a ref giving a bad decision at a game, a child playing with a box of matches, a garda pulling up someone for pissing in a dark alley etc.
The Cloonchas is the area of Cloonbonnive and Gortaganny in West Roscommon where most townlands begin with 'Cloon', eg. Cloonfower, Clooncan. From the Irish for meadows, 'Cluainte'.