Words That Rhyme With "Efficacy" :

2 syllables:

assay, bassi, brassey, brassie, brassy, cassie, chassis, classy, gassy, glassy, grassy, Kasey, lassie, Massey, massy, sassy, tassie, vasey

4 syllables:

graphicacy, Tallahassee

5 syllables:

inefficacy