substitution

noun

sub·​sti·​tu·​tion ˌsəb-stə-ˈtü-shən How to pronounce substitution (audio)
-ˈtyü-
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
substitutional adjective
substitutionally adverb
substitutionary adjective

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.
On 72 minutes, Antonio Conte made a triple substitution. James Horncastle, New York Times, 30 Sep. 2025 The desire for more speed also could impact the Celtics’ substitution patterns, according to Walsh, who was part of the C’s squad that experimented with a quicker tempo during the NBA Summer League. Zack Cox, Boston Herald, 29 Sep. 2025 Speaking to reporters for the first time since the opener, Prince on Friday took responsibility for the late substitutions that contributed to two damaging delay of game penalties late in the Week 2 loss against the Patriots. Barry Jackson, Miami Herald, 26 Sep. 2025 Without electrification, Simpliciano said, renewable targets run the risk of being feeble and ineffective, with brands potentially turning to biomass and other problematic substitutions as stopgap measures. Jasmin Malik Chua, Sourcing Journal, 25 Sep. 2025 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 4 Oct. 2025.

Medical Definition

substitution

noun
sub·​sti·​tu·​tion ˌsəb-stə-ˈt(y)ü-shən How to pronounce substitution (audio)
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

substitution

noun
sub·​sti·​tu·​tion ˌsəb-stə-ˈtü-shən, -ˈtyü- How to pronounce substitution (audio)
: 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
substitutional adjective
substitutionary adjective
Last Updated: - Updated example sentences
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