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

Almost three-fourths of kindergarteners who test in the bottom 20% of students for readiness exams remain in the bottom 20% of their class by fifth grade, according to The Children’s Reading Foundation, a nonprofit organization. —CNN Money, 26 Feb. 2026

Another White 3-pointer — his fourth of the half — erased the Suns’ double-digit lead. —Zack Cox, Boston Herald, 25 Feb. 2026

Sam Hauser shot 6 for 14, including 4 for 10 from 3-point range, to add 16 points and the Celtics - playing without All-Star Jaylen Brown (right knee contusion) - won their fourth in a row and for the ninth time in their last 10 games. —CBS News, 25 Feb. 2026

Shots that weren’t falling in the first three quarters found the bottom of the net in the fourth. —John Maffei, San Diego Union-Tribune, 25 Feb. 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