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 noun day 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 pronoun I'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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The first known use of one was before the 12th century
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