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
Cite this Entry
“Fourth.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/fourth. Accessed 1 Sep. 2026.
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