[kuh n-vur-zhuh n, -shuh n]
See more synonyms for conversion on
  1. the act or process of converting; state of being converted.
  2. change in character, form, or function.
  3. spiritual change from sinfulness to righteousness.
  4. change from one religion, political belief, viewpoint, etc., to another.
  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 francs 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. change from realty into personalty, or vice versa, as in the sale or purchase of land or mining 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.Compare breeding(def 6).
  16. Computers.
    1. the process of changing software designed to run on one computer system to run on another.
    2. the change from an existing computer system to a new computer system.
    3. the act of transferring or copying data stored on one storage medium to another storage medium.
    4. the process of changing the base that a number or numbers are written in.
  17. the transformation of material from a form suitable for printing by one process to a form suitable for another process: a halftone gravure conversion.

Origin of conversion

1300–50; Middle English conversio(u)n (< Anglo-French) < Latin conversiōn- (stem of conversiō) a complete change. See converse2, -ion
Related formscon·ver·sion·al, con·ver·sion·ar·y [kuh n-vur-zhuh-ner-ee, -shuh-] /kənˈvɜr ʒəˌnɛr i, -ʃə-/, adjectivenon·con·ver·sion, nounpre·con·ver·sion, nounsem·i·con·ver·sion, noun Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2018

Examples from the Web for conversion

Contemporary Examples of conversion

Historical Examples of conversion

British Dictionary definitions for conversion


    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 expressionthe 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. NZ the unauthorized appropriation of a motor vehicle
Derived Formsconversional or conversionary, adjective

Word Origin for conversion

C14: from Latin conversiō a turning around; see convert
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

Word Origin and History for conversion

mid-14c., originally of religion, from French conversion, from Latin conversionem (nominative conversatio), noun of action from past participle stem of convertere (see convert (v.)). General sense of "transformation" is early 15c. Of buildings, from 1921. Conversion disorder "hysteria" (attested from 1946 but said to have been coined by Freud) was in DSM-IV (1994).

Online Etymology Dictionary, © 2010 Douglas Harper

conversion in Medicine


[kən-vûrzhən, -shən]
  1. The acquisition by bacteria of a new property associated with presence of a prophage.
  2. A defense mechanism in which repressed ideas, conflicts, or impulses are manifested by various bodily symptoms, such as paralysis or breathing difficulties, that have no physical cause.
Related formscon•versive (-sĭv) adj.
The American Heritage® Stedman's Medical Dictionary Copyright © 2002, 2001, 1995 by Houghton Mifflin Company. Published by Houghton Mifflin Company.