D defs.my
Entry 1 sense Webster, 1913

Memento mori

/mĭm-ĕn'-tō môr'-ē/ · Me·men·to mo·ri · IPA /məˌmɛntoʊ ˈmɔːɹi/
01 Lit., remember to die, i.e., that you must die; a warning to be prepared for death; an object, as a death's-head or a personal ornament, us…
  1. 1.
    Lit., remember to die, i.e., that you must die; a warning to be prepared for death; an object, as a death's-head or a personal ornament, usually emblematic, used as a reminder of death.