### Definition of Involution

**1.** *Noun.* Reduction in size of an organ or part (as in the return of the uterus to normal size after childbirth).

**2.**

*Noun.*A long and intricate and complicated grammatical construction.

**3.**

*Noun.*Marked by elaborately complex detail.

**Elaborateness**,

**Elaboration**,

**Intricacy**

Generic synonyms:

**Complexity**,

**Complexness**

Derivative terms:

**Elaborate**,

**Elaborate**

**4.**

*Noun.*The act of sharing in the activities of a group. "The teacher tried to increase his students' engagement in class activities"

**Engagement**,

**Involvement**,

**Participation**

Generic synonyms:

**Group Action**

Specialized synonyms:

**Commitment**,

**Intercession**,

**Intervention**,

**Group Participation**

Derivative terms:

**Engage**,

**Involve**,

**Involve**,

**Participate**,

**Participate**

Antonyms:

**Non-engagement**,

**Non-involvement**,

**Nonparticipation**

**5.**

*Noun.*The process of raising a quantity to some assigned power.

**Exponentiation**

Generic synonyms:

**Mathematical Operation**,

**Mathematical Process**,

**Operation**

**6.**

*Noun.*The action of enfolding something.

### Definition of Involution

**1.** *n.* The act of involving or infolding.

### Definition of Involution

**1.** Noun. entanglement; a spiralling inwards; intricacy ¹

**2.** Noun. (mathematics) An endofunction whose square is equal to the identity function; a function equal to its inverse. ¹

**3.** Noun. (physiology) The regressive changes in the body occurring with old age. ¹

**4.** Noun. (mathematics obsolete) A power: the result of raising one number to the power of another. ¹

¹ *Source: wiktionary.com*

### Definition of Involution

**1.** [n -S]

### Medical Definition of Involution

**1.**
1. A rolling or turning inward.
2. One of the movements involved in the gastrulation of many animals.
3. A retrograde change of the entire body or in a particular organ, as the retrograde changes in the female genital organs that result in normal size after delivery.
4. The progressive degeneration occurring naturally with advancing age, resulting in shrivelling of organs or tissues.
Origin: L. Involutio, volvere = to roll
This entry appears with permission from the Dictionary of Cell and Molecular Biology
(11 Mar 2008)

### Involution Pictures

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### Lexicographical Neighbors of Involution

### Literary usage of Involution

Below you will find example usage of this term as found in modern and/or classical literature:

**1.** *Encyclopaedia Britannica: A Standard Work of Reference in Art, Literature* (1907)

"30. bee« of a four-Bide are six points in **involution**, the projections of ...
The theory of **involution** may at once be extended from the row to the flat and ..."**2.** *Projective Geometry* by Linnaeus Wayland Dowling (1917)

"A cyclic projectivity of order 2 on any form is called an **involution** on ...
Thus, two protectively related and superposed forms constitute an **involution** on ..."**3.** *A Treatise on Conic Sections: Containing an Account of Some of the Most* by George Salmon (1879)

"Again, the reciprocal of six points in **involution** is a pencil in **involution**.
The greater part of the equations already found apply equally to lines drawn ..."**4.** *A Dictionary of Science, Literature, & Art: Comprising the Definitions and* by George William Cox (1866)

"Thus, in an **involution** of the second order, if о denote the point whose conjugate
is at ... If in any **involution** whatever, the harmonic centre be taken, ..."**5.** *The Encyclopaedia Britannica: A Dictionary of Arts, Sciences and General* (1890)

"Is positive OF Is real, and has two values, equal and opposite. The **involution**
Is hyperbolic. If e-.O, OF-O, and the two foci both Coincide with'the centre. ..."**6.** *Catalogue of Scientific Papers, 1800-1900: Subject Indexby Royal Society (Great Britain), Herbert McLeod* by Royal Society (Great Britain), Herbert McLeod (1908)

"**involution**. Terquem, Ü. NA Mth. 12 (1853) 24-. Hesse, LO [1863] (vu) Crelle J.
63 (1864) ... **involution** common to group of 5 lines and system of 9 planes. ..."**7.** *An Introduction to the Ancient and Modern Geometry of Conics: Being a* by Charles Taylor (1881)

"&c. are to be regarded as positive, and the **involution** is said to be ... In a
positive **involution** there are two points Fund F' (on opposite sides of the ..."