Entry 1 sense Webster, 1913 Peccadillo · Pec·ca·dil·lo · IPA /ˌpɛ.kəˈdɪ.loʊ/ 01 n. A slight trespass or offense; a petty crime; a trifling fault. pl. Peccadillos ((#)) 1. A slight trespass or offense; a petty crime; a trifling fault.