#early microscopy

• Animalcule — A historical and archaic term used in the past (especially by early microscopists of the 17th and 18th centuries) to designate a microscopic living organism, such as a protozoan, bacterium, rotifer, or spermatozoon. This structural conceptual naming was proposed by Antonie van Leeuwenhoek to describe the tiny moving forms observed in water droplets through his primitive lenses, later replaced by modern microbiological terminology.