Yes, submarine is playable
...and is worth 17 points.
Found in the following dictionaries
Enable (Words with friends)
SOWPODS (Collins Scrabble Words)
OTCWL2014 (NASPA Word List 2014)
TWL06 (NASPA List 2006)
"Submarine" Definition
noun
A large sandwich consisting of a long roll split lengthwise and filled with layers of meat, cheese, tomatoes, lettuce, and condiments. Also called sub1; also called regionally Cuban sandwich, grinder, hero, hoagie, Italian sandwich, poor boy, torpedo, wedge, zep.
Nautical A vessel that is capable of operating submerged. Also called sub1.
Something that functions or operates underwater.
A naval vessel designed to operate underwater.
A large sandwich on a long split roll with any of a variety of fillings (as meatballs or cold cuts, cheese, lettuce, and tomato) .
verb-transitive
Baseball To pitch (a ball) with an underhand motion.
Sports To knock down with a blow to the legs.
To attack by submarine, especially with torpedoes.
adjective
Beneath the surface of the water; undersea.
verb-intransitive
To slide, drive, or throw under something.
verb
To attack by or as if by a submarine attack from beneath.
To dive or slide under something.
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