Diddle/ˈdɪdl/ Definition 1 of 4Pro Tip 1/2Colloquial Usage Used informally, might not be suitable for business or official settings. That rogue diddled his clients out of their savings. Pro Tip 2/2Negative Connotation Implies dishonest actions; used to express disapproval. Everyone knows he's likely to diddle you if you're not careful.