Definition:
- (a.) Following the thirty-ninth, or preceded by thirty-nine units, things, or parts.
- (a.) Constituting one of forty equal parts into which anything is divided.
- (n.) One of forty equal parts into which one whole is divided; the quotient of a unit divided by forty; one next in order after the thirty-ninth.
Compare fortieth with other words:
fortieth vs. line
fortieth vs. forty