Merriam-Webster Logo
SINCE 1828
Menu
dictionary thesaurus

rotary pump

noun

Definition of rotary pump

: a valveless pump in which the fluid is positively pushed by meshing vanes on parallel revolving shafts and meshing screws into the discharge pipe

Love words?

You must — there are over 200,000 words in our free online dictionary, but you are looking for one that’s only in the Merriam-Webster Unabridged Dictionary.

Start your free trial today and get unlimited access to America's largest dictionary, with:

  • More than 250,000 words that aren't in our free dictionary
  • Expanded definitions, etymologies, and usage notes
  • Advanced search features
  • Ad free!

First Known Use of rotary pump

1799, in the meaning defined above

Keep scrolling for more

Learn More about rotary pump

Statistics for rotary pump

Look-up Popularity

Time Traveler for rotary pump

The first known use of rotary pump was in 1799

See more words from the same year

Comments on rotary pump

What made you want to look up rotary pump? Please tell us where you read or heard it (including the quote, if possible).

Show Comments  Hide Comments 

WORD OF THE DAY

misprision

Listen to the pronounciation of misprision

concealment of treason or felony

Get Word of the Day daily email!

Test Your Vocabulary

The Exceptions Quiz III

  • one green toy robot amidst many red toy robots
  • Which of these words does not mean "nonsense"?
Spell It

Can you spell these 10 commonly misspelled words?

TAKE THE QUIZ
SCRABBLE® Sprint

Test Your Knowledge - and learn some interesting things along the way.

TAKE THE QUIZ
Love words? Need even more definitions?

Subscribe to America's largest dictionary and get thousands more definitions and advanced search—ad free!

Words at Play
Ask the Editors
Word Games