Yes, lay is playable
...and is worth 6 points.
Found in the following dictionaries
Enable (Words with friends)
SOWPODS (Collins Scrabble Words)
OTCWL2014 (NASPA Word List 2014)
TWL06 (NASPA List 2006)
"Lay" Definition
noun
A narrative poem, such as one sung by medieval minstrels; a ballad.
The amount of such twist.
The direction the strands of a rope or cable are twisted in: a left lay.
The state of one that lays eggs: a hen coming into lay.
verb-transitive
Games To place (a bet); wager.
To aim (a gun or cannon).
To cause to be in a particular condition: The remark laid him open to criticism.
To cause to lie down: lay a child in its crib.
phrasal-verb
Lay about To strike blows on all sides.
Lay aside To give up; abandon: lay aside all hope of rescue.
Lay aside To save for the future.
Lay away To put aside and hold for future delivery.
Lay away To reserve for the future; save.
idiom
Lay down the law To assert positively and often arrogantly.
Lay it on thick Informal To exaggerate; overstate.
Lay it on thick Informal To flatter effusively.
Lay of the land The nature, arrangement, or disposition of something.
Lay rubber Slang To accelerate a motor vehicle suddenly from a halt to a high speed, thereby spinning the wheels and depositing on the road a thin film of burned rubber from the rear tire or tires.
verb-intransitive
Nautical To put oneself into the position indicated.
To engage energetically in an action.
To produce and deposit eggs.
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