Definition of "animalcula" [animalcula]

• Plural of animalculum.
• [capitalized] A loose synonym of Infusoria.

The Century Dictionary (Public Domain)

• "I confess, however, there is a very great difficulty in imagining any one spot to be the birthplace of the millions of millions of animalcula and confervae: for whence come the germs at such points?"
• "Parts of the lake seen from a short distance appeared of a reddish colour, and this perhaps was owing to some infusorial animalcula."
• "Some of the water placed in a glass was of a pale reddish tint; and, examined under a microscope, was seen to swarm with minute animalcula darting about, and often exploding."