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

After flying out in his next two trips to the plate, Murakami launched a two-run home run — his team-leading fifth of the season — in the ninth inning. —Meghan Montemurro, Chicago Tribune, 17 Apr. 2026

Each is near or on agricultural land, with at least one-fifth of the surrounding area used for grazing fields or crops, and would together supply about 20 gigawatts of electricity if built. —ABC News, 17 Apr. 2026

The cost spiked due to a slowdown in traffic through the Strait of Hormuz, a key artery for oil shipments through which one-fifth of the world's oil supply normally flows. —Mary Cunningham, CBS News, 17 Apr. 2026

With nearly one-fifth of the vote (18%), Swalwell was one point ahead of Republican Steve Hilton and had a 4-point lead over the next two Democrats, Katie Porter and Tom Steyer. —Douglas Schoen, Oc Register, 17 Apr. 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