- next after the eighty-ninth; being the ordinal number for 90.
- being one of 90 equal parts.
- a ninetieth part, especially of one (1/90).
- the ninetieth member of a series.
Origin of ninetieth
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2018
Examples from the Web for ninetieth
Neither retirement nor a ninetieth birthday slowed his publication rate.The Best of Brit Lit
August 27, 2010
He died at Rome, on February 18, 1564, in the ninetieth year of his age.
The colonel of the Ninetieth Rhode Island fell at twenty-two.Special Messenger
Robert W. Chambers
In full-front view he did not look like a man in his ninetieth year.In and Around Berlin
Minerva Brace Norton
Theophrastus began his "Character of Man" on his ninetieth birthday.Genius in Sunshine and Shadow
Maturin Murray Ballou
He began it in his fortieth year, and did not finish it until his ninetieth .The Queer, the Quaint and the Quizzical
Frank H. Stauffer
- (usually prenominal)
- being the ordinal number of ninety in numbering or counting order, position, time, etc. Often written: 90th
- (as noun)the ninetieth in succession
- one of 90 approximately equal parts of something
- (as modifier)a ninetieth part
- the fraction equal to one divided by 90 (1/90)
Word Origin and History for ninetieth
Online Etymology Dictionary, © 2010 Douglas Harper