means A short written record or message meant to capture information, remind, or communicate something briefly; also a single musical tone or a remark of observation.

from From Latin 'nota,' meaning a mark, sign, or token — the kind of scratch you'd make to flag something worth remembering. It passed through Old French 'note' into English, carrying its family of relatives along: 'notable' (worth marking), 'notice' (the marking), and 'notation' (the act of it). The musical sense and the written-reminder sense both grow from that same root idea — a mark that stands in for a thing, so the thing isn't lost.