fourth

noun

ˈfȯrth 

plural fourths ˈfȯr(th)s 

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

Varsho redeemed himself in the fourth. —Andy McCullough, New York Times, 25 Oct. 2025

The Kings led by 20 in the first half of the game but were outscored 36-21 in the third quarter and 30-24 in the fourth. —Marcus Smith, Sacbee.com, 24 Oct. 2025

Along with imposing new requirements that could impact the Medicaid eligibility of millions of Californians, one-fourth of county residents utilize Medi-Cal. —Devan Patel, Mercury News, 23 Oct. 2025

Three-fourths of Americans support term limits for Supreme Court justices, with over 67 percent of Republicans in agreement, according to a new Public Religion Research Institute (PRRI) poll. —Mandy Taheri, MSNBC Newsweek, 22 Oct. 2025

Word History

Etymology

see four

First Known Use

1594, in the meaning defined at sense 2

Phrases Containing fourth

• a poor second/third/fourth
• fourth dimension
• fourth estate
• fourth trimester
• fourth wall
• fourth world
• sixty-fourth note
• sixty-fourth rest

Rhymes for fourth

• henceforth
• thenceforth

Kids Definition

fourth

noun

ˈfō(ə)rth 

ˈfȯ(ə)rth

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