fifteenth

American  

[fif-teenth] / ˈfɪfˈtinθ /

adjective

1. next after the fourteenth; being the ordinal number for 15.

2. being one of 15 equal parts.

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noun

1. a fifteenth part, especially of one (1/15).

2. the fifteenth member of a series.

3. Music. the interval of two octaves.

fifteenth British  

/ ˈfɪfˈtiːnθ /

adjective

1. 1. coming after the fourteenth in order, position, time, etc. Often written: 15th

   2. ( as noun )

      the fifteenth of the month

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noun

1. 1. one of 15 equal or nearly equal parts of something

   2. ( as modifier )

      a fifteenth part

2. the fraction equal to one divided by 15 ( 1/ 15 )

3. 1. an interval of two octaves

   2. one of two notes constituting such an interval in relation to the other, esp the one higher in pitch

   3. an organ stop of diapason quality sounding a note two octaves higher than that normally produced by the key depressed; a two-foot stop

Etymology

Origin of fifteenth

before 900; Middle English fiftenthe ( fifteen, -th ² ); replacing Middle English fiftethe, Old English fīftēotha

Example Sentences

The farmer, who is calling for tougher penalties for livestock worrying, said this the the fourteenth or fifteenth such attack at his farm.

From BBC • Jan. 29, 2026

By the late fifteenth century, however, the lines originally drawn in biblical maps began spreading into maps of the wider world.

From Science Daily • Nov. 30, 2025

In 1965, Congress passed the Voting Rights Act — the subtitle of which, Keyssar points out, is “an act to enforce the fifteenth amendment.”

From Salon • Nov. 25, 2025

On the fifteenth floor sits Per Sundin, chief executive of Pophouse Entertainment which runs the museum.

From BBC • Mar. 14, 2024

It began in the fifteenth century and lasted barely a hundred years before being smashed by Spain.

From "1491" by Charles C. Mann