Fif"teenth` (?), a. [OE. fiftenthe; cf. fiftethe, AS. fīfteōða. See Fifteen.] 1. Next in order after the fourteenth; -- the ordinal of fifteen.

2. Consisting of one of fifteen equal parts or divisions of a thing.

Fif"teenth`, n. 1. One of fifteen equal parts or divisions; the quotient of a unit divided by fifteen.

2. A species of tax upon personal property formerly laid on towns, boroughs, etc., in England, being one fifteenth part of what the personal property in each town, etc., had been valued at. Burrill.

3. (Mus.) (a) A stop in an organ tuned two octaves above the diaposon. (b) An interval consisting of two octaves.

• The ordinal form of the number fifteen.
  
• The person or thing in the fifteenth position.
  
• One of fifteen equal parts of a whole.