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conversion

American  
[kuhn-vur-zhuhn, -shuhn] / kənˈvɜr ʒən, -ʃən /

noun

  • conversions
    plural
  1. the act or process of converting; state of being converted.

  2. a change in character, form, or function.

  3. a change from one religion, political belief, viewpoint, etc., to another.

  4. a thoroughgoing spiritual change that involves repentance and a turn toward God or right living.

  5. a change of attitude, emotion, or viewpoint from one of indifference, disbelief, or antagonism to one of acceptance, faith, or enthusiastic support, especially such a change in a person's religion.

  6. a physical transformation from one material or state to another.

    conversion of coal, water, and air into nylon.

  7. the act of obtaining equivalent value, as of money or units of measurement, in an exchange or calculation.

    conversion of yen into dollars.

  8. a physical, structural, or design change or transformation from one state or condition to another, especially to effect a change in function.

    conversion of a freighter into a passenger liner.

  9. a substitution of one component for another so as to effect a change.

    conversion from oil heat to gas heat.

  10. Mathematics. a change in the form or units of an expression.

  11. Logic. the transposition of the subject and predicate of a proposition, as “No good man is unhappy” becomes by conversion “No unhappy man is good.”

  12. Law.

    1. unauthorized assumption and exercise of rights of ownership over personal property belonging to another.

    2. a change from realty into personalty, or vice versa, as in the sale or purchase of land or the mining of coal.

  13. Football. a score made on a try for a point after touchdown by place-kicking or drop-kicking the ball over the bar between the goalposts or by completing a pass in or running the ball into the end zone.

  14. Psychoanalysis. the process by which a repressed psychic event, idea, feeling, memory, or impulse is represented by a bodily change or symptom.

  15. Physics. the production of radioactive material in a process in which one nuclear fuel is converted into another by the capture of neutrons.

  16. Digital Technology. a performance metric for a website that counts the percentage of visitors that engage in the intended purpose of the site, as making a purchase or signing a petition.

    The site was redesigned to simplify user interactions and optimize conversion.

  17. Computers.

    1. Also called data conversion.  the act or process of transferring data from one format into another.

    2. Also called media conversion.  the act of transferring or copying stored data from one storage medium to another.

    3. porting.

    4. Also called system conversion.  the change from an existing computer system to a new computer system.

    5. the process of changing the base that a number or numbers are written in.

  18. the transformation of material from a form suitable for printing by one process to a form suitable for another process.

    a halftone gravure conversion.


conversion British  
/ kənˈvɜːʃən /

noun

    1. a change or adaptation in form, character, or function

    2. something changed in one of these respects

  1. a change to another attitude or belief, as in a change of religion

  2. maths a change in the units or form of a number or expression

    the conversion of miles to kilometres involves multiplying by 1.61

  3. logic a form of inference by which one proposition is obtained as the converse of another proposition

  4. law

    1. unauthorized dealing with or the assumption of rights of ownership to another's personal property

    2. the changing of real property into personalty or personalty into realty

  5. rugby a score made after a try by kicking the ball over the crossbar from a place kick

  6. physics a change of fertile material to fissile material in a reactor

    1. an alteration to a car engine to improve its performance

    2. ( as modifier )

      a conversion kit

  7. material alteration to the structure or fittings of a building undergoing a change in function or legal status

  8. the unauthorized appropriation of a motor vehicle

"Collins English Dictionary — Complete & Unabridged" 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

Other Word Forms

Derived Forms

Inflected Forms

Nouns

Etymology

Origin of conversion

First recorded in 1300–50; Middle English conversio(u)n from Anglo-French, from Latin conversiōn- (stem of conversiō ) “a turning around, revolution”; see converse 2, -ion

Explanation

Something that is transformed from one state or form to another has had a conversion. The twentieth century saw the conversion from outhouses to indoor plumbing. You may oversee the conversion of your attic into an extra bedroom. The noun conversion can be used to describe some very specific transformations. If you exchange euros for dollars, you have made a monetary conversion. If your Canadian friend tells you, "It was warm today! It got up to 28!" and you figure out that 28 degrees in Celsius is the same as 82 degrees in Fahrenheit, then you have made a mathematical conversion. If you change your religion, you've had a religious conversion.

Keep Reading on Vocabulary.com

Vocabulary lists containing conversion

Example Sentences

Examples are provided to illustrate real-world usage of words in context. Any opinions expressed do not reflect the views of Dictionary.com.

See Examples For:

At Chelsea, his shot conversion rate dropped to just 2.8%, scoring only once in the league from an xG of 4.5.

From BBC Aug. 27, 2026

We initially thought a conversion meant paying taxes when withdrawing money from the traditional IRA and then effectively paying taxes again when contributing the money to the Roth.

From MarketWatch Aug. 25, 2026

A near-partial collapse last month at America’s largest office-to-residential conversion project in Midtown Manhattan is bringing new scrutiny to this booming development strategy.

From The Wall Street Journal Aug. 17, 2026

They would then have to undergo a conversion from matter into energy and back into matter, producing new baryons that move outward perpendicular to the beam.

From Science Daily Aug. 16, 2026

It is not enough to give lip service and to believe in equal pay: there has to be a conversion, from the heart.

From "Cat's Eye" by Margaret Atwood

And if a saver has low-income years before required withdrawals kick in, say after retirement, Roth conversions could make sense then.

From The Wall Street Journal Aug. 21, 2026

Nineteen Manhattan office buildings have begun conversions so far this year, and another 17 are planned, according to Cushman & Wakefield.

From The Wall Street Journal Aug. 17, 2026

The key question is whether the tax you pay on those conversions now is lower than the marginal tax cost you are likely to face later.

From MarketWatch Aug. 15, 2026

So you have two years to make those Roth conversions count.

From MarketWatch Aug. 15, 2026

After the destruction of Tenochtitlan, the Spanish court and intellectual elite were convulsed with argument for a century about whether the conversions were worth the suffering inflicted.

From "1491" by Charles C. Mann

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