early 13c., "observe, mark carefully," from O.Fr. noter, from L. notare, from nota "letter, note," originally "a mark, sign," possibly an alteration of Old L. *gnata, infl. by gnoscere "to recognize." Meaning "to set in writing" is from c.1400. The noun is first attested c.1300, in the musical sense; meaning "brief writing" is from 1540s. Notebook is first attested 1570s; noteworthy is from 1550s.