Intersubstitutability

[suhb-sti-toot, -tyoot] /ˈsʌb stɪˌtut, -ˌtyut/

noun
1.
a person or thing acting or serving in place of another.
2.
(formerly) a person who, for payment, served in an army or navy in the place of a conscript.
3.
Grammar. a word that functions as a replacement for any member of a class of words or constructions, as do in He doesn’t know but I do.
verb (used with object), substituted, substituting.
4.
to put (a person or thing) in the place of another.
5.
to take the place of; replace.
6.
Chemistry. to replace (one or more elements or groups in a compound) by other elements or groups.
verb (used without object), substituted, substituting.
7.
to act as a substitute.
adjective
8.
of or relating to a substitute or substitutes.
9.
composed of substitutes.
/ˈsʌbstɪˌtjuːt/
verb
1.
(often foll by for) to serve or cause to serve in place of another person or thing
2.
(chem) to replace (an atom or group in a molecule) with (another atom or group)
3.
(logic, maths) to replace (one expression) by (another) in the context of a third, as replacing x + y for x in 3x = k gives 3x + 3y = k
noun
4.

5.
(grammar) another name for pro-form
6.
(Canadian) another name for supply teacher
7.
(nautical) another word for repeater (sense 5)
8.
(formerly) a person paid to replace another due for military service
v.

early 15c. in transitive sense, 1888 as intransitive, from Latin substitutus, past participle of substituere (see substitution). Related: Substituted; substituting.
n.

“one who acts in place of another,” early 15c., from Old French substitute and directly from Latin substitutus, past participle of substituere (see substitution). Team sports sense is from 1849.