Yes, reason is playable
...and is worth 7 points.
Found in the following dictionaries
Enable (Words with friends)
SOWPODS (Collins Scrabble Words)
OTCWL2014 (NASPA Word List 2014)
TWL06 (NASPA List 2006)
"Reason" Definition
noun
A declaration made to explain or justify action, decision, or conviction: inquired about her reason for leaving.
A normal mental state; sanity: He has lost his reason.
An underlying fact or cause that provides logical sense for a premise or occurrence: There is reason to believe that the accused did not commit this crime.
Good judgment; sound sense.
Logic A premise, usually the minor premise, of an argument.
idiom
In reason With good sense or justification; reasonably.
With reason With good cause; justifiably.
Within reason Within the bounds of good sense or practicality.
verb-intransitive
Obsolete To engage in conversation or discussion.
To talk or argue logically and persuasively.
To use the faculty of reason; think logically.
verb-transitive
To determine or conclude by logical thinking: reasoned out a solution to the problem.
To persuade or dissuade (someone) with reasons.
verb
To take part in conversation, discussion, or argument.
To talk with another so as to influence actions or opinions .
To use the faculty of reason so as to arrive at conclusions.
To justify or support with .
To persuade or influence by the use of reason.
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