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Webster 1913 Edition
Millionth
Mil′lionth
,Adj.
Being the last one of a million of units or objects counted in regular order from the first of a series or succession; being one of a million.
Mil′lionth
,Noun.
The quotient of a unit divided by one million; one of a million equal parts.
Webster 1828 Edition
Millionth
MILL'IONTH
,Adj.