1. reminder, memento (of a person, occasion, etc.). souvenirsou`ve*nir (? or ?), n. [f., fr. souvenir to remember, fr. l. subvenire to come up, come to mind; sub under + venire to come, akin to e. come. see: come, and cf. subvention.] that which serves as a reminder; a remembrancer; a memento; a keepsake.souvenir n