<p><strong>Noun</strong></p><ul><li>A large mop used on shipboard for cleaning decks, living quarters, etc.</li><li>A bit of sponge, cloth, cotton, or the like, sometimes fixed to a stick, for cleansing the mouth of a sick person or for applying medicaments, drying areas, etc.</li><li>The material collected with a swab as a specimen for microscopic study.</li><li>A brush or wad of absorbent material for cleaning the bore of a firearm.</li><li>Slang. a sailor; swabby.</li><li>Slang. a clumsy fellow.</li></ul><p><strong>Verb</strong></p><ul><li>(used with object) to clean with or as if with a swab: to swab the decks.</li><li>To take up or apply, as moisture, with or as if with a swab: to swab soapy water from the decks.</li><li>To pass over a surface: to swab a mop over the decks.</li></ul>