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

Beckman took the lead in the fourth behind the exquisite play of Qusai Azem, who scored 22 of his game-high 26 in the second half and 13 in the fourth. —Martin Henderson, Oc Register, 27 Jan. 2026

Andrew moved ahead 17-16 at halftime and there were five lead changes in the third quarter before Brother Rice locked things down, holding the Thunderbolts without a field goal in the fourth. —Steve Millar, Chicago Tribune, 27 Jan. 2026

Los Angeles maintained its lopsided advantage in the third quarter and was ahead 96-66 headed into the fourth. —Los Angeles Times, 26 Jan. 2026

Brooklyn edged the quarter 29-28 behind Dëmin’s 3-for-6 shooting, but the Nets still faced a 30-point hole entering the fourth. —C.j. Holmes, New York Daily News, 26 Jan. 2026

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