ninth

noun

ˈnīn(t)th 

plural ninths ˈnīn(t)s 

ˈnīn(t)ths

1

: one that is number nine in a series

They're leaving on the ninth.

The batter hit a home run in the bottom of the ninth.

see Table of Numbers

2

: one of nine equal parts of something

She owned a ninth of the company.

3

a

: a musical interval embracing an octave and a second

b

: the tone at this interval

c

: a chord containing a ninth

ninth adjective or adverb

the ninth day of the month

the book's ninth edition

He finished ninth in the race.

Examples of ninth in a Sentence

Recent Examples on the Web

The prototype achieved more than a 100-fold increase in inference speed while relying on only about one-ninth of the compute power of a commercial GPU. — Neetika Walter, Interesting Engineering, 13 July 2026

Kevin Ginkel pitched a perfect eighth and Paul Sewald a perfect ninth for his 21st save. — ABC News, 10 July 2026

Ceddanne Rafaela made a diving catch to help closer Aroldis Chapman finish off a rapid 1-2-3 ninth. — Gabrielle Starr, Boston Herald, 9 July 2026

After starter Luinder Avila gave up four runs in four innings, Royals relievers Steven Cruz (2-2), Beck Way, Lucas Erceg, Matt Strahm and Alex Lange combined to allow only two baserunners over the final five, with Lange pitching a perfect ninth for his seventh save. — CBS News, 28 June 2026

Word History

First Known Use

13th century, in the meaning defined at sense 2

Phrases Containing ninth

• ninth cranial nerve

Kids Definition

ninth

noun

ˈnīn(t)th 

plural ninths

: one that is number nine in a series see number

ninth adjective or adverb