Definition of preformative:
(n) :
(chiefly in Semitic languages) a formative letter, syllable, etc., at the beginning of a word.
(adj) :
(grammar, chiefly in Semitic languages) of a letter, syllable, etc.: attached to the beginning of a word as a formative element.
(adj) :
Of a thing: forming or affecting something that comes later.
(adj) :
Of or pertaining to preformation.
(n) :
Misspelling of performative. [A performative utterance.]