Memento
Noun. From the Latin memento.
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1. Prayer in the canon of the Mass beginning with this word, in which the priest commemorates the living or the dead for whom he is praying.
2. Mortuary image intended to keep alive the memory of a deceased person and bearing the mention “Remember in your prayers…”.
3. Mark or note intended to help recall something to memory.
4. Short notice summarising what is essential and must not be forgotten.
5. Elementary manual recording the key notions of a discipline, science or technique.
6. Notebook in which one writes down useful information so as not to forget it.
7. Memento(-)mori: devotional object representing a human skull or fleshless head, designed to encourage meditation on death.