ˌinfyəˈz]ōrēə, -ˈs], -ȯr- noun plural
Etymology: New Latin, from neuter plural of infusorius, from Latin infusus (past participle of infundere to pour in) + -orius -ory
1. capitalized : a group of minute organisms typically found in infusions of decaying organic matter:
a. in early classifications : a heterogeneous group comprising various plant and animal organisms (as bacteria, algae, fungi, protozoans, and small metazoans)
b. in later classifications : a heterogeneous group of animals comprising protozoans and small metazoans
c. in early modern classifications : a major division of Protozoa comprising protozoans with differentiated locomotor organelles and including the ciliates
d. in some recent classifications : a class of Protozoa coextensive with the subphylum Ciliophora
2. often capitalized : microscopic animal life — not used technically