1
: one that is number four in a series
I was the fourth to arrive.
They arrive on the fourth. [=the fourth day of the month]
see Table of Numbers
2
: one of four equal parts of something : quarter entry 1
Cut the cake into fourths.
a fourth of the population
3
a
: a musical interval (see interval sense 2) embracing four tones of the diatonic scale
b
: a tone at this interval
specifically : subdominant sense 1
c
: the harmonic combination of two tones a fourth apart
4
: the fourth forward gear or speed of a motor vehicle
shifted into fourth
5
the Fourth : July 4 observed as a legal holiday in the U.S. in commemoration of the adoption of the Declaration of Independence in 1776 : fourth of july
watched fireworks on the Fourth

called also Independence Day

fourth adjective or adverb
the fourth edition of a book
the fourth tallest mountain
fourthly adverb
Fourthly, don't sing a whole opera through … —Mark Twain

Examples of fourth in a Sentence

cut the cake into fourths She drank a fourth of the bottle.
Recent Examples on the Web
Examples are automatically compiled from online sources to show current usage. Read More Opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback.
But Giovanni Marcantoni, Volo's founder and CEO, told CNBC that about three-fourths of its growth has come from organic expansion, rather than through acquisitions, as more Americans look for ways to build community. — Alex Harring,brandon Gomez, CNBC, 30 Oct. 2026 Inside the numbers Roughly three-fourths of club revenues on average are derived from a centralized pot of money distributed by the league’s owner and operator, the Board of Control for Cricket in India (BCCI). — Justin Birnbaum, Sportico.com, 28 Oct. 2026 Boston surged as Brooklyn’s offense stalled, hitting eight 3s in the third quarter and taking an 86-82 lead into the fourth. — C.j. Holmes, New York Daily News, 27 Oct. 2026 McKee had a pass intercepted by linebacker DeMarvion Overshown late in the fourth. — CBS News, 27 Oct. 2026 See All Example Sentences for fourth

Word History

Etymology

see four

First Known Use

1594, in the meaning defined at sense 2

Time Traveler
The first known use of fourth was in 1594

Cite this Entry

“Fourth.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/fourth. Accessed 31 Oct. 2026.

Kids Definition

1
: one that is number four in a series see number
2
: the difference in pitch between the first tone and the fourth tone of a scale
fourth adjective or adverb
fourthly adverb

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