twenty-first

[ twen-tee-furst, twuhn- ]
/ ˈtwɛn tiˈfɜrst, ˈtwʌn- /

adjective

next after the twentieth; being the ordinal number for 21.
being one of 21 equal parts.

noun

a twenty-first part, especially of one (1/21).
the twenty-first member of a series.
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2020

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