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

oxygen cycle

noun

Definition of oxygen cycle

  1. :  the cycle whereby atmospheric oxygen is converted to carbon dioxide in animal respiration and regenerated by green plants in photosynthesis



1935

First Known Use of oxygen cycle

1935


Learn More about oxygen cycle


Seen and Heard

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

WORD OF THE DAY

a smart aleck

Get Word of the Day daily email!

WORD GAMES

Take a 3-minute break and test your skills!

image567572573

Which of these is a synonym of unctuous?

maudlin angry prompt oily
Name That Thing

Test your visual vocabulary with our 10-question challenge!

TAKE THE QUIZ
SCRABBLE® Sprint

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

TAKE THE QUIZ