keepsake (n.)
"anything kept or given to be kept for the sake of the giver; a token of friendship," 1790, from keep (v.) + sake (n.1); an unusual formation on model of namesake; thus an object kept for the sake of the giver. The word was used c. 1830s in titles of popular holiday gift books containing beautiful engravings and mediocre poetry. As an adjective by 1839.