Definition of thirty-first
(Entry 1 of 2)
1 : being number 31 in a countable series
the thirty-first day — see Table of Numbers
2 : being one of 31 equal parts into which anything is divisible
a thirty-first share of the money
thirty-first
noun\ " \
Definition of thirty-first (Entry 2 of 2)
1 : number 31 in a countable series
the thirty-first of the month
2 : the quotient of a unit divided by 31 : one of 31 equal parts of anything
one thirty-first of the total
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