- A breathing apparatus used by swimmers and skin divers, consisting of a long tube held in the mouth. (noun)
- A retractable vertical tube in a diesel-engine submarine that contains air-intake and exhaust pipes for the engines and for ventilation, permitting extended periods of submergence at periscope depth. (noun)
- To dive using a snorkel. (verb-intransitive)
American Heritage(R) Dictionary of the English Language, Fifth Edition. Copyright (c) 2011 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.