ninetieth

1 of 2

adjective

nine·​ti·​eth ˈnīntē|ə̇th 

-ti|

1

: being number 90 in a countable series

the ninetieth day

see Table of Numbers

2

: being one of 90 equal parts into which something is divisible

a ninetieth share of the money

ninetieth

2 of 2

noun

"

plural -s

1

: number 90 in a countable series

2

: the quotient of a unit divided by 90 : one of 90 equal parts of something

one ninetieth of the total

Word History

Etymology

Adjective

Middle English nyntithe, from Old English nigontigotha, from nigontig ninety + -otha, -tha -th

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