From WordNet (r) 2.0 (August 2003) [wn]:
souvenir
n 1: something of sentimental value [syn: keepsake, token,
relic]
2: a reminder of past events [syn: memento]
From The Collaborative International Dictionary of English v.0.48 [gcide]:
Souvenir \Sou`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.
[1913 Webster]