ˌsəbztəˈtüshən, -bst-, -tə.ˈtyü- noun
( -s )
Usage: often attributive
Etymology: Middle English substitucion, from Middle French substitution, from Late Latin substitution-, substitutio, from Latin substitutus (past participle of substituere to substitute) + -ion, -io -ion
1. : the substituting of one person or thing for another: as
a. Roman law
(1) : the nomination of someone to be heir upon the failure of an heir previously named to take an inheritance — called also common substitution, vulgar substitution
(2) : the similar nomination of a person to take as heir in place of or to succeed a descendant under puberty and in the potestas of the testator in case of the descendant's failure to take the inheritance or on his death before puberty or to succeed a descendant of any age who is a lunatic
(3) : a designation by a testator that names one to whom property is to be handed over by the person named as heir or by his heir and that gives rise to a fideicommissum ; also : a designation under civil law of a person to succeed to another as beneficiary of an estate used as a means of settling property and involving a fideicommissum
b. : the replacing of a quantity by its equal or of a variable by a value of it or of an algebraic expression or function by one that is equal in value
c.
(1) : a chord that produces an unexpected or less likely resolution in place of a likelier resolution
(2) : a change of fingers on a digital of a keyboard instrument
d. : 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
the substitution of one chlorine atom for one hydrogen atom of methane gives methyl chloride
— often contrasted with addition ; compare exchange 2e
e. : the replacing of a linguistic form by a substitute in a context
f.
(1) : the replacing in Greek or Latin prosody of a foot required or expected at a given place in a given meter by another which is equivalent in temporal quantity
(2) : the using in a metrical series in modern prosody of a foot other than the prevailing foot of the series or of a silence that replaces expected sound and occupies the time of a foot or syllable — compare inversion , ionic displacement
g.
(1) : the deceptive replacing of one material or product by another of less worth
(2) : the natural economic tendency for the less costly of two or more operations or agencies to replace the more costly
h.
(1) : the turning from an obstructed desire to another desire whose gratification is socially acceptable
(2) : the turning from an obstructed form of behavior to a different and often more primitive expression of the same tendency
a substitution neurosis
(3) : 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
2. : something that functions as a substitute or exists in a particular relation as a result of an act of substituting: as
a. : material substituted
the substitution was found to be harmless
b. : a sound change consisting in the replacement or apparent replacement of one vowel or consonant by another
c. : an instance of linguistic substitution
d. : a cipher or method of ciphering that replaces message letters or polygraphs with substitutes