Dictionary
Thesaurus
Medical
Scrabble®
Spanish Central
Browse DictionaryBrowse Thesaurus
Get our free apps!iPhone•iPad•Android
Games
Word of the Day
Video
Blog: Words at Play
My Faves
Dictionary

U–boat

noun \ˈyü-ˌbōt\

: a German submarine

Full Definition of U-BOAT

:  a German submarine
See U–boat defined for English-language learners
See U-boat defined for kids
ADVERTISEMENT

Origin of U-BOAT

translation of German U-boot, short for Unterseeboot, literally, undersea boat
First Known Use: 1916

Learn More About U-BOAT

Browse

Next Word in the Dictionary: U–boltPrevious Word in the Dictionary: ubi supraAll Words Near: U-boat
ADVERTISEMENT
10 Charming Words for Nasty People
Put-downs with flair
Learn More
When "Literally" isn't, well, literal
How to use a word that (literally) drives some people nuts.
Watch Now
Know what this is?
Test your vocab with our fun, fast game
Go Play
Fear of cats?
Ailurophobia, and 9 other unusual fears
Learn More
Join Us
Merriam-Webster
on Facebook
Merriam-Webster
on Twitter
Bookstore: Digital and Print
Merriam-Webster references for Mobile, Kindle, print, and more.
See All
Other Merriam-Webster Dictionaries