“Hydroxy-Indol(e)Acetic Acid”

We have one entry that includes the term Hydroxy-Indol(e)Acetic Acid.

5-hydroxyindoleacetic acid

noun

: a metabolite C10H9NO3 of serotonin that is present in cerebrospinal fluid and in urine —abbreviation 5-HIAA

See the full definition

Word of the Day

Listen to the pronunciation of sonorous

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
Name That Thing

You know what it looks like… but what is it called?

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 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?
The Missing Letter A daily crossword with a twist
vintage ad illustration of a smiling woman
Brand Name Vocabulary Quiz You’re gonna need some moxie to ace this quiz
See All