Definitions

1. noun

A hypothetical type of microorganism, especially a virus, that is considered to be the smallest living thing.

“According to the new theory, the microzoon is the fundamental building block of all life on Earth.”

2. noun

A hypothetical microorganism of the smallest possible size, used in thought experiments to test hypotheses about the nature of living things.

“The scientist proposed the existence of a microzoon to explain the origins of life on our planet.”