invert

American  

[in-vurt, in-vurt] / ɪnˈvɜrt, ˈɪn vɜrt /

verb (used with object)

1. to turn upside down.

2. to reverse in position, order, direction, or relationship.

3. to turn or change to the opposite or contrary, as in nature, bearing, or effect.

   to invert a process.

4. to turn inward or back upon itself.

5. to turn inside out.

6. Chemistry. to subject to a reaction in which a starting material of one optical configuration forms a product of the opposite configuration.

7. Music. to subject to musical inversion, the transposition between the upper voice part and the lower.

8. Phonetics. to articulate as a retroflex vowel.

---

verb (used without object)

1. Chemistry. to undergo a reaction in which a starting material of one optical configuration forms a product of the opposite configuration.

adjective

1. Chemistry. subjected to a reaction in which a starting material of one optical configuration forms a product of the opposite configuration.

noun

1. a person or thing that is reversed in position, changed to the contrary, or turned upside down, inside out, or inward.

2. (in plumbing) that portion of the interior of a drain or sewer pipe where the liquid is deepest.

3. a U-shaped arch or vault, having the opposite vertical orientation compared to a traditional arch or vault.

4. Philately. a two-colored postage stamp with all or part of the central design printed upside down in relation to the inscription.

5. Psychiatry. (no longer in technical use)

   1. a gay person.

   2. a person whose behavior is considered nonnormative for their assigned sex, historically involving both gender non-conforming or transgender expression and gay or lesbian sexual orientation.

6. Disparaging and Offensive. anyone whose sexuality or gender expression is regarded as strange or unnatural, especially a gay or transgender person.

7. Informal. (especially among aquarists) invertebrate.

   My invert tank is mostly sea slugs, but I bought a couple of shrimp recently also.

invert British  

verb

1. to turn or cause to turn upside down or inside out

2. (tr) to reverse in effect, sequence, direction, etc

3. (tr) phonetics

   1. to turn (the tip of the tongue) up and back

   2. to pronounce (a speech sound) by retroflexion

4. logic to form the inverse of a categorial proposition

---

noun

1. psychiatry

   1. a person who adopts the role of the opposite sex

   2. another word for homosexual

2. architect

   1. the lower inner surface of a drain, sewer, etc Compare soffit

   2. an arch that is concave upwards, esp one used in foundations

Related Words

See reverse.

Other Word Forms

• invertibility noun
• invertible adjective
• noninverted adjective
• uninverted adjective

Etymology

Origin of invert

First recorded in 1525–35; from Latin invertere “to turn upside down or inside out,” equivalent to in- “in” + vertere “to turn”; in- ², verse

Example Sentences

This caused the VIX futures curve to invert.

From MarketWatch • Mar. 3, 2026

Buffett would later invert that payment model, in what became the defining pursuit of his investment career—capitalizing on the insurance industry.

From Barron's • Dec. 12, 2025

It was time to invert one of the most fundamental shots in the sport.

From The Wall Street Journal • Oct. 29, 2025

A lot of the pleasure and the point of “Sleep Dealer” was to invert preconceptions about the future.

From Los Angeles Times • Apr. 9, 2025

“We were all trying to solve this quadric the same way, and then I realized we just had to invert the way we were looking at it.”

From "Tradition" by Brendan Kiely