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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Time Traveler for reason
The first known use of reason was in the 13th century
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