substitutional

/ˌsʌbstɪˈtuʃənəl/
adjective
  1. Relating to or involving the act of replacing one thing with another.
    • The coach made a substitutional change, putting in a fresh player for the second half.
    • In chemistry, a substitutional reaction occurs when one atom replaces another in a molecule.
    • The substitutional use of cheaper materials lowered the cost of the product.
Synonyms