The word is animalcule. Pronounced \an-uh-MAL-kyool\. This word is a noun, and is defined as
A minute or microscopic animal, nearly or quite invisible to the naked eye.
Used in a sentence: My place in the scheme of things pertaining to my existence and all that the Father is and has created shows I am animalcule in comparison, yet still important to God as is all of His creatures.