prefixed; prefixing; prefixes

Definition of prefix

 (Entry 1 of 3)

transitive verb

1 \ (ˌ)prē-​ˈfiks How to pronounce prefix (audio) \ : to fix or appoint beforehand
2 \ ˈprē-​ˌfiks How to pronounce prefix (audio) , prē-​ˈfiks \ [partly from prefix entry 2] : to place in front especially : to add as a prefix prefix a syllable to a word


pre·​fix | \ ˈprē-ˌfiks How to pronounce prefix (audio) \

Definition of prefix (Entry 2 of 3)

1 : an affix attached to the beginning of a word, base, or phrase and serving to produce a derivative word or an inflectional form — compare suffix
2 : a title used before a person's name


pre·​fix | \ ˈprē-ˌfiks How to pronounce prefix (audio) \

Definition of prefix (Entry 3 of 3)

: characterized by placement of an operator before its operand or before its two operands if it is a binary operator — compare infix, postfix

Other Words from prefix


prefixal \ ˈprē-​ˌfik-​səl How to pronounce prefix (audio) , prē-​ˈfik-​ \ adjective

What are prefixes, suffixes, and combining forms?


Prefixes and suffixes are both kinds of affixes. That is, they are word parts that attach to the beginning or end of a word or word base (a word stripped down to its simplest form) to produce a related word or an inflectional form of a word. Examples are in- in informal and both re- and -ing in reporting.

A third kind of affix is called an infix. Infixes are inserted into a word or word base. English uses very few infixes, but a couple examples are the plural-making s in words like cupsful and passersby, and various swear words, like damn in informal constructions like guaran-damn-tee.

A combining form is a form of a word that only appears as part of another word. There are a number of kinds of combining forms, each classified by what kind of word results when the form is used. For example, -wise in clockwise is an adverb combining form; -like in birdlike is an adjective combining form; -graph in photograph is a noun combining form; and -lyze in electrolyze is a verb combining form.

Combining forms are similar to affixes but can have a bit more lexical substance to them. Unlike affixes, combining forms are substantial enough to form a word simply by connecting to an affix, such as when the combining form cephal- joins with the suffix -ic to form cephalic. A combining form can also differ from an affix in its being derived from an independent word. For example, para- is a combining form in the word paratrooper because in that word it represents the word parachute. Para- is a prefix, however, in the words paranormal and paramedic. A combining form can also be distinguished historically from an affix by the fact that it is borrowed from another language in which it is descriptively a word or a combining form, such as the French mal giving English the mal- in malfunction.

Examples of prefix in a Sentence

Verb Prefix “un” to “do” to form the word “undo.” The cost of the item was prefixed by a dollar sign. Noun Add the prefix “re-” to form the words “retell” and “recall.”
Recent Examples on the Web: Verb In this case, the length of the clue is prefixed by the hash (#) symbol. Quanta Magazine, 21 Dec. 2018 Recent Examples on the Web: Noun Trillium are one of the most easily recognizable spring blooms; the tri- prefix in their name is a reminder to look for flowers with three white petals and three broad leaves. Chelsey Lewis, Milwaukee Journal Sentinel, 28 Apr. 2022 And Twitter has two blog posts explaining its decision to label state-media accounts, one of which includes a prefix that calls out China specifically. Eamon Barrett, Fortune, 26 Apr. 2022 There is no hard-and-fast rule on when to use a hyphen after a pre- or post- prefix. WSJ, 5 Apr. 2022 Currently, only the brown M&M has a prefix — Ms. Brown — on the M&M website. Alexandra Larkin, CBS News, 21 Jan. 2022 Ka, a one-letter Hebrew prefix that could easily be overlooked, teaches – as does the moon – that the darkest moments contain sparks of hope. Rabbi Avi Weiss,, 3 Jan. 2022 The prefix ka can be interpreted in a range of ways, providing a key to the true meaning of this phrase. Rabbi Avi Weiss,, 3 Jan. 2022 The negation as a prefix signals this part of our identity is never enough. Ching Ching Tan, CNN, 18 Dec. 2021 Many of the numbers in the six affected area codes begin with the 988 prefix. Timothy Fanning, San Antonio Express-News, 28 Oct. 2021 See More

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'prefix.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

First Known Use of prefix


15th century, in the meaning defined at sense 1


1646, in the meaning defined at sense 1


1971, in the meaning defined above

History and Etymology for prefix


Middle English, from Middle French prefixer, from Latin praefixus


New Latin praefixum, from Latin, neuter of praefixus, past participle of praefigere to fasten before, from prae- + figere to fasten — more at fix

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The first known use of prefix was in the 15th century

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Cite this Entry

“Prefix.” Dictionary, Merriam-Webster, Accessed 28 May. 2022.

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More Definitions for prefix


pre·​fix | \ ˈprē-ˌfiks How to pronounce prefix (audio) \

Kids Definition of prefix

: a letter or group of letters that comes at the beginning of a word and has its own meaning

More from Merriam-Webster on prefix

Nglish: Translation of prefix for Spanish Speakers

Britannica English: Translation of prefix for Arabic Speakers


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