fifth

American  

[fifth, fith] / fɪfθ, fɪθ /

adjective

1. next after the fourth; being the ordinal number for five.

2. being one of five equal parts.

3. Automotive. of, relating to, or operating at the gear transmission ratio at which the drive shaft speed is greater than that of fourth gear for a given engine crankshaft speed.

   fifth gear.

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adverb

1. in the fifth place; fifthly.

noun

1. a fifth part, especially of one (1/5).

2. the fifth member of a series.

3. a fifth part of a gallon of liquor or spirits; 4/5 (0.8) of a quart (about 750 milliliters).

4. Automotive. fifth gear.

5. Music.

   1. a tone on the fifth degree from another tone (counted as the first).

   2. the interval between such tones.

   3. the harmonic combination of such tones.

idioms

1. plead the Fifth, to decline on the basis of the Fifth Amendment to the U.S. Constitution to answer a question when testifying. Also take the Fifth

fifth British  

/ fɪfθ /

adjective

1. 1. coming after the fourth in order, position, time, etc. Often written: 5th

   2. ( as noun )

      he came on the fifth

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noun

1. 1. one of five equal or nearly equal parts of an object, quantity, measurement, etc

   2. ( as modifier )

      a fifth part

2. the fraction equal to one divided by five ( 1/ 5 )

3. music

   1. the interval between one note and another five notes away from it counting inclusively along the diatonic scale

   2. one of two notes constituting such an interval in relation to the other See also perfect diminished interval

4. an additional high gear fitted to some motor vehicles

adverb

1. Also: fifthly.  after the fourth person, position, event, etc

1. Also: fifthly.  as the fifth point: linking what follows with the previous statements, as in a speech or argument

fifth More Idioms  

More idioms and phrases containing fifth

• take the fifth

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Etymology

Origin of fifth

First recorded before 1000; earlier fift, Middle English fifte, Old English fīfta; -th by analogy with fourth, etc.

Example Sentences

That discrepancy excited physicists because it hinted at the possibility of undiscovered particles or even a new "fifth force" beyond the four known fundamental forces.

From Science Daily • May 19, 2026

Even though a ceasefire has been declared, fuel prices have remained high as the Strait of Hormuz, where a fifth of the world's oil passes through, is still blocked.

From BBC • May 18, 2026

A wildfire sparked by the flare of a shipwrecked mariner has burned nearly a fifth of Santa Rosa Island and marks what officials called the largest blaze recorded on the island in modern history.

From Los Angeles Times • May 18, 2026

Legislation allowing prospective CPAs to bypass a fifth year of school has them deciding whether to skip a master’s to start making money sooner and save on tuition.

From The Wall Street Journal • May 18, 2026

Out of the eight periods a day, I only saw Tina in three—language arts first period, lunch fifth period and science seventh period.

From "Liar, Liar" by Gary Paulsen