Definition of reason
(Entry 1 of 2)
1a
: a statement offered in explanation or justification
gave reasons that were quite satisfactory
b
: a rational ground or motive
a good reason to act soon
c
: the thing that makes some fact intelligible : cause
the reason for earthquakes the real reason why he wanted me to stay— Graham Greene
d
: a sufficient ground of explanation or of logical defense
especially
: something (such as a principle or law) that supports a conclusion or explains a fact
the reasons behind her client's action
2a(1)
: the power of comprehending, inferring, or thinking especially in orderly rational ways : intelligence
(2)
: proper exercise of the mind
(3)
: sanity
b
: the sum of the intellectual powers
3
archaic
: treatment that affords satisfaction
reason
verbDefinition of reason (Entry 2 of 2)
1
: to use the faculty of reason so as to arrive at conclusions
2a
: to talk with another so as to influence actions or opinions
can't reason with them
b
obsolete
: to take part in conversation, discussion, or argument
1
: to discover, formulate, or conclude by the use of reason
a carefully reasoned analysis
2
: to persuade or influence by the use of reason
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Merriam-Webster unabridged
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Time Traveler for reason
The first known use of reason was in the 13th century
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