Catachresis (kat-a-kree’-sis): The use of a word in a context that differs from its proper application. This figure is generally considered a vice; however, Quintilian defends its use as a way by which one adapts existing terms to applications where a proper term does not exist.
I am spellbound with gratitude.
Definition courtesy of “Silva Rhetoricae” (rhetoric.byu.edu).