Mercenary rhymes with:
cardiopulmonary, cautionary, centenary, concessionary, confectionary, confectionery, coronary, counterrevolutionary, deflationary, dictionary, disciplinary, discretionary, disinflationary, diversionary, evolutionary, exclusionary, expansionary, expeditionary, extraordinary, functionary, illusionary, imaginary, inflationary, interdisciplinary, luminary, missionary, noninflationary, ordinary, preliminary, probationary, pulmonary, reactionary, recessionary, revolutionary, seminary, stationary, stationery, urinary, veterinary, visionary