Living organism (such as a bacteria, fungi, viruses) too small to be seen with naked eye but visible under a microscope. Also called microbe.

Use microorganism in a sentence

  • The astronauts were shocked and excited to discover a new species of microorganism on their most recent trip to the moon.

    22 people found this helpful
  • The lake has has it's own ecosystem, it all starts from the microorganism to the top of the food chain.

    20 people found this helpful
  • Under the microscope, we could see the microorganism and it was really interesting to study its behavior and how it worked.

    17 people found this helpful
Show more usage examples...


Browse by Letter: # A B C D E F G H I J K L M N O P Q R S T U V W X Y Z