Animalcule ('little animal', from

Latin Latin (, or , ) is a classical language belonging to the Italic branch of the Indo-European languages. Latin was originally a dialect spoken in the lower Tiber area (then known as Latium) around present-day Rome, but through the power of the ...

''animal'' + the diminutive suffix ''-culum'') is an old term for

microscopic organisms A microorganism, or microbe,, ''mikros'', "small") and ''organism'' from the el, ὀργανισμός, ''organismós'', "organism"). It is usually written as a single word but is sometimes hyphenated (''micro-organism''), especially in olde ...

that included

bacteria Bacteria (; singular: bacterium) are ubiquitous, mostly free-living organisms often consisting of one Cell (biology), biological cell. They constitute a large domain (biology), domain of prokaryotic microorganisms. Typically a few micrometr ...

protozoans Protozoa (singular: protozoan or protozoon; alternative plural: protozoans) are a group of single-celled eukaryotes, either free-living or parasitic, that feed on organic matter such as other microorganisms or organic tissues and debris. Histo ...

, and very small

animals Animals are multicellular, eukaryotic organisms in the biological kingdom Animalia. With few exceptions, animals consume organic material, breathe oxygen, are able to move, can reproduce sexually, and go through an ontogenetic stage in ...

. The word was invented by 17th-century Dutch scientist Antonie van Leeuwenhoek to refer to the microorganisms he observed in rainwater. Some better-known types of animalcule include: * '' Actinophrys'', and other

heliozoa Heliozoa, commonly known as sun-animalcules, are microbial eukaryotes ( protists) with stiff arms ( axopodia) radiating from their spherical bodies, which are responsible for their common name. The axopodia are microtubule-supported projections f ...

, termed sun animalcules. * ''

Amoeba An amoeba (; less commonly spelled ameba or amœba; plural ''am(o)ebas'' or ''am(o)ebae'' ), often called an amoeboid, is a type of cell or unicellular organism with the ability to alter its shape, primarily by extending and retracting pseudop ...

'', termed ''Proteus'' animalcules. * '' Noctiluca scintillans'', commonly termed the sea sparkles. * ''

Paramecium '' ''Paramecium'' ( , ; also spelled ''Paramoecium'') is a genus of eukaryotic, unicellular ciliates, commonly studied as a representative of the ciliate group. ''Paramecia'' are widespread in freshwater, brackish, and marine environments and a ...

'', termed slipper animalcules. * '' Rotifers'', termed wheel animalcules. * ''

Stentor In Greek mythology, Stentor (Ancient Greek: Στέντωρ; ''gen''.: Στέντορος) was a herald of the Greek forces during the Trojan War. Mythology Stentor is mentioned briefly in Homer's ''Iliad'' in which Hera in the guise of Stent ...

'', termed trumpet animalcules. * ''

Vorticella ''Vorticella'' is a genus of bell-shaped ciliates that have stalks to attach themselves to substrates. The stalks have contractile myonemes, allowing them to pull the cell body against substrates. The formation of the stalk happens after the fr ...

'', and other

peritrich The peritrichs (Latin: Peritrichia) are a large and distinctive group of ciliates. The peritrichs were first defined by Friedrich von Stein in 1859. Initially they were considered spirotrichs, then treated as a separate category, before receivi ...

s, termed bell animalcules. The concept seems to have been proposed at least as early as about 30 BC, as evidenced by this translation from

Marcus Varro Marcus Terentius Varro (; 116–27 BC) was a Roman polymath and a prolific author. He is regarded as ancient Rome's greatest scholar, and was described by Petrarch as "the third great light of Rome" (after Vergil and Cicero). He is sometimes calle ...

's ''Rerum Rusticarum Libri Tres'':

Note also if there be any swampy ground, both for the reasons given above, and because certain minute animals, invisible to the eye, breed there, and, borne by the air, reach the inside of the body by way of the mouth and nose, and cause diseases which are difficult to be rid of.

The term was also used during the 17th century by

Henry Oldenburg Henry Oldenburg (also Henry Oldenbourg) FRS (c. 1618 as Heinrich Oldenburg – 5 September 1677), was a German theologian, diplomat, and natural philosopher, known as one of the creators of modern scientific peer review. He was one of the fo ...

, the first Secretary of the

Royal Society The Royal Society, formally The Royal Society of London for Improving Natural Knowledge, is a learned society and the United Kingdom's national academy of sciences. The society fulfils a number of roles: promoting science and its benefits, re ...

and founding editor of '' Philosophical Transactions'', to translate the Dutch words used by van Leeuwenhoek to describe microorganisms that he discovered. In Gilbert and Sullivan's ''

The Pirates of Penzance ''The Pirates of Penzance; or, The Slave of Duty'' is a comic opera in two acts, with music by Arthur Sullivan and libretto by W. S. Gilbert. Its official premiere was at the Fifth Avenue Theatre in New York City on 31 December 187 ...

'', the word appears in adjectival form in the ' Major-General's Song', in which Major-General Stanley sings, 'I know the

scientific names In taxonomy, binomial nomenclature ("two-term naming system"), also called nomenclature ("two-name naming system") or binary nomenclature, is a formal system of naming species of living things by giving each a name composed of two parts, bot ...

of beings animalculous...' The term continued to be current at least as late as 1879.

References

{{Antonie van Leeuwenhoek Zoology Antonie van Leeuwenhoek Biology and natural history in the Dutch Republic

See also

References