CO2 Get Printable Handwriting Hear It! Say It! Write It! Learn It! Spelling Test Definition noun. a colorless gas that plants use for photosynthesis. Example Sentence The level of CO2 in the atmosphere is increasing due to human activities. More Example Sentences CO2 is important for plant growth. Synonyms carbon dioxide; gas; air Antonyms oxygen; fresh air Hear It! Say It! Write It! CO2 Switch to cursive Start Share with your friends:
