equivocation (n.) Look up equivocation at Dictionary.com
late 14c., "the fallacy of using a word in different senses at different stages of the reasoning" (a loan-translation of Greek homonymia, literally "having the same name"), from Old French equivocation, from Late Latin aequivocationem (nominative aequivocatio), from aequivocus "of identical sound," past participle of aequivocare, from aequus "equal" (see equal (adj.)) + vocare "to call" (see voice (n.)).