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Definition of one
(Entry 1 of 4)
1 : being a single unit or thing one day at a time She is one year old.
2a : being one in particular early one morning The Grand Canyon is one place I'd like to visit.
b : being preeminently what is indicated one fine person She is one tough teacher.
3a : being the same in kind or quality both of one species "Puma" and "cougar" are different names for one animal.
b(1) : constituting a unified entity of two or more components The combined elements form one substance.
(2) : being in agreement or union am one with you on this
4a : some sense 1 will see you again one day
b : being a certain individual specified by name one John Doe made a speech
5 : only sense 2a the one person she wanted to marry
one
nounDefinition of one (Entry 2 of 4)
1 : the first whole number above zero — see Table of Numbers
2 : the number denoting unity
3a : the first in a set or series —often used with an attributive nounday one
b : an article of clothing of a size designated one wears a one
4 : a single person or thing has the one but needs the other
5 : a one-dollar bill
at one for one
: at harmony : in a state of agreement
: as one example I for one disagree
one
pronounDefinition of one (Entry 3 of 4)
1 : a certain indefinitely indicated person or thing saw one of his friends
2a : an individual of a vaguely indicated group : anyone at all one never knows
b —used as a third person substitute for a first person pronounI'd like to read more but one doesn't have the time.
3 : a single instance of a specified action felt like belting him one— John Casey
-one
noun suffixDefinition of -one (Entry 4 of 4)
: ketone or related or analogous compound or class of compounds lactone quinone
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A More Exception(al) Quiz
- Which of the following words is not a synonym for ‘a young person’?
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Can you spell these 10 commonly misspelled words?
TAKE THE QUIZ
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Merriam-Webster unabridgedWords at Play
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Time Traveler for one
The first known use of one was before the 12th century
See more words from the same century