mid-14c., "quality of being excellent or rare," from Old French nobilite "high rank; dignity, grace; great deed" (12c., Modern French nobilité), and directly from Latin nobilitatem (nominative nobilitas) "celebrity, fame; high birth; excellence, superiority; the nobles," from nobilis "well-known, prominent" (see noble, adj.). Meaning "quality of being of noble rank or birth" is attested from late 14c.; sense of "noble class collectively" is from 1520s.