“proton pump”

We have one entry that includes the term proton pump.

proton pump inhibitor

noun

: any of a group of drugs that inhibit the activity of pumps transporting hydrogen ions across cell membranes and are used to inhibit gastric acid secretion

See the full definition

Word of the Day

Listen to the pronunciation of frugal

See Definitions and Examples »

Test Your Vocabulary

Name That Flower

  • any of a genus helianthus especially h annuus of new world composite plants with large yellow rayed flower heads bearing edible seeds that yield an edible oil
True or False

Test your knowledge - and maybe learn something along the way.

TAKE THE QUIZ
Play Blossom: Solve today's spelling word game by finding as many words as you can using just 7 letters. Longer words score more points.

Pick the best words!

PLAY
Love words? Need even more definitions?

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

Games & Quizzes

See All
Play Quordle: Guess all four words in a limited number of tries. Each of your guesses must be a real 5-letter word.
Quordle Can you solve 4 words at once?
Play Blossom: Solve today's spelling word game by finding as many words as you can using just 7 letters. Longer words score more points.
Blossom Word Game Pick the best words!
Play Missing Letter: a crossword with a twist. Each of the 25 puzzle words start with a different letter of the alphabet. Which letter is missing?
Missing Letter A daily crossword with a twist
sweet smart pug puppy dog sitting in front of blackboard with chalk question marks
Commonly Confused Words Quiz Vol. 3 Do you have a (flare/flair) for choosing the righ...