Yes, counter is playable
...and is worth 12 points.
Found in the following dictionaries
Enable (Words with friends)
SOWPODS (Collins Scrabble Words)
OTCWL2014 (NASPA Word List 2014)
TWL06 (NASPA List 2006)
"Counter" Definition
noun
A flat surface on which money is counted, business is transacted, or food is prepared or served.
A stiff piece of leather around the heel of a shoe.
An imitation coin; a token.
Games A piece, as of wood or ivory, used for keeping a count or a place.
adjective
Contrary; opposing: moves and counter moves on the checkerboard.
Marked by or tending toward or in an opposite direction or effect.
Given to or marked by opposition, hostility, or antipathy.
Situated or lying opposite .
Recalling or ordering back by a superseding contrary order .
adverb
In a contrary manner or direction.
To or toward an opposite or dissimilar course or outcome: a method running counter to traditional techniques.
In an opposite or wrong direction.
To or toward a different or opposite direction, result, or effect .
idiom
Over the counter Without being listed or available on an officially recognized stock exchange but traded in direct negotiation between buyers and sellers: bought stocks over the counter.
Under the counter In an illegal or surreptitious manner; illicitly: arrested for selling prescription drugs under the counter.
verb-transitive
To meet or return (a blow) by another blow.
To move or act in opposition to; oppose.
To offer in response: countered that she was too busy to be thorough.
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