Synonyms for Submarine (same or very similar meaning)
WordNet sense 1 (a large sandwich made of a long crusty roll split lengthwise and filled with meats and cheese (and tomato and onion and lettuce and condiments); different names are used in different sections of the United States):
bomber, grinder, hero, hoagie, hoagy, sub, torpedo, wedge, zep, Cuban sandwich, hero sandwich, Italian sandwich, submarine sandwich
WordNet sense 2 (a submersible warship usually armed with torpedoes):
pigboat, U-boat
WordNet sense 3 (beneath the surface of the sea):
undersea
WordNet sense 4 (beneath the surface):
subsurface
From the ODE community, based on WordNet
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