fifth

noun

ˈfith  ˈfif(t)th 

ˈfift

plural fifths ˈfiths 

ˈfif(t)ths, 

ˈfif(t)s

1

: one that is number five in a series

Payment is due on the fifth of the month.

see Table of Numbers

2

: one of five equal parts of something

spent a fifth of their income on rent

3

a

: the musical interval embracing five diatonic degrees

b

: a tone at this interval

specifically : dominant sense 1

c

: the harmonic combination of two tones at this interval

4

: a unit of measure for liquor equal to one fifth of a U.S. gallon (0.757 liter)

5

the Fifth : the Fifth Amendment of the U.S. Constitution

also : the right accorded by the Fifth Amendment to refuse to testify against oneself see also plead the fifth, take the fifth

fifth adjective or adverb

the fifth annual food festival

She finished fifth in the race.

fifthly adverb

Fourthly, it takes a lot of concrete to make a nuclear power plant. Fifthly, there is no place to put the waste that is safe.

—Victor Odlivak

Examples of fifth in a Sentence

The bill is due on the fifth of each month.

She donated a fifth of her income to charity.

bought a fifth of whiskey

Recent Examples on the Web

Tankers are seen at the Khor Fakkan Container Terminal, the only natural deep-sea port in the region and one of the major container ports in the Sharjah Emirate, along the Strait of Hormuz, a waterway through which one-fifth of global oil output passes on June 23, 2025. —Lee Ying Shan, CNBC, 12 Jan. 2026

Doncic scored 12 points in the third quarter but also committed four fouls in the period, including his fifth of the game. —CBS News, 10 Jan. 2026

Taken together, the costs to remove Ashworth, Ten Hag and the latter’s assistants were equal to two-fifths of the costs incurred on staffing changes at United last season. —Chris Weatherspoon, New York Times, 9 Jan. 2026

Almost one-fifth of young adults reported taking on extra work to cover health care or insurance costs for IBD, a significantly higher rate than the 11% of both adults and caregivers who reported the same. —Theresa Gaffney, STAT, 7 Jan. 2026

Word History

Etymology

Middle English fifte, fifthe, from Old English fīfta, from fīf five

First Known Use

1557, in the meaning defined at sense 2

Phrases Containing fifth

• fifth column
• fifth disease
• fifth wheel
• plead the fifth

Kids Definition

fifth

noun

ˈfith  ˈfif(t)th 

1

: one that is number five in a series see number

2

: the difference in pitch between the first tone and the fifth tone of a scale

fifth adjective or adverb

fifthly adverb