substitution

noun

Synonyms of substitutionnext
1
a
: the act, process, or result of substituting one thing for another
b
: replacement of one mathematical entity by another of equal value
2
: one that is substituted for another
substitutionally adverb

Examples of substitution in a Sentence

The coach made three substitutions in the second half of the game. I'd prefer rice with my steak instead of potatoes, but the menu says “no substitutions.” Substitution of applesauce for oil is one way of reducing the fat in recipes. The cookbook has a long list of substitutions for ingredients that may be hard to find.
Recent Examples on the Web
Examples are automatically compiled from online sources to show current usage. Read More Opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback.
The skills with almost no potential for substitution were those grounded in human relationships. Dan Fitzpatrick, Forbes.com, 11 July 2026 Yet Spain’s final substitution, which brought on Merino in the 86th minute, wasn’t the only one that figured heavily in the result. Kevin Baxter, Los Angeles Times, 10 July 2026 Belgium has now made all five of its substitutions, with Kevin De Bruyne coming off, so Rudi Garcia is out of cards to play. Aleks Klosok, CNN Money, 10 July 2026 Courtois made four saves, but the Real Madrid keeper went down to the grass four minutes before his substitution. ABC News, 10 July 2026 See All Example Sentences for substitution

Word History

Etymology

Middle English substitucion, from Middle French, from Late Latin substitution-, substitutio, from substituere

First Known Use

14th century, in the meaning defined at sense 1a

Time Traveler
The first known use of substitution was in the 14th century

Browse Nearby Words

Cite this Entry

“Substitution.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/substitution. Accessed 12 Jul. 2026.

Medical Definition

substitution

noun
1
: a chemical reaction in which one or more atoms or groups in a molecule are replaced by equivalent atoms or groups to form at least two products
especially : the replacement of hydrogen in an organic compound by another element or group
2
a
: the turning from an obstructed desire to another desire whose gratification is socially acceptable
b
: the turning from an obstructed form of behavior to a different and often more primitive expression of the same tendency
a substitution neurosis
c
: the reacting to each of a set of stimuli by a response prescribed in a key
a substitution test for speed of learning new responses

Legal Definition

: the substituting of one person or thing for another: as
a
in the civil law of Louisiana : a disposition not in trust by which a donee, heir, or legatee is charged to hold property transferred and return it to a third person compare fidei commissum, vulgar substitution

Note: Substitutions are prohibited.

b
: replacement of a party to an action with a successor or representative upon motion to the court when the party is unable to continue litigating (as because of death, incompetency, transfer of interest, or loss of the office for which the party was suing or being sued in an official capacity)
c
: the replacement of a new agreement or obligation for an old one see also novation
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