Quantcast
Merriam-Webster Logo
  • Dictionary
  • Thesaurus
  • Medical
  • Scrabble
  • Spanish Central
  • Learner's Dictionary

diatom

play
noun di·a·tom \ˈdī-ə-ˌtäm\

Definition of diatom

  1. :  any of a class (Bacillariophyceae) of minute planktonic unicellular or colonial algae with silicified skeletons that form diatomaceous earth



Origin of diatom

ultimately from Greek diatomos cut in half, from diatemnein to cut through, from dia- + temnein to cut — more at tome


First Known Use: 1845


Medical Dictionary

diatom

play
noun di·a·tom \ˈdī-ə-ˌtäm\

Medical Definition of diatom

  1. :  any of a class (Bacillariophyceae) of minute planktonic unicellular or colonial algae with silicified skeletons that form diatomite




Learn More about diatom

  1. Medical Dictionary: Definition of "diatom" Britannica.com: Encyclopedia article about "diatom"


Seen and Heard

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

WORD OF THE DAY

February 8, 2016

to clear from accusation or blame

Get Word of the Day daily email!

WORD GAMES

Take a 3-minute break and test your skills!

image1037863653

Which of the following refers to thin, bending ice, or to the act of running over such ice?

pince-nez kittly-benders duvet spindrift
Name That Thing

10 quick questions: hear them, spell them, and see how your skills compare to the crowd.

TAKE THE QUIZ
SCRABBLE® Sprint

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

TAKE THE QUIZ