Mammoth Uncensored Word List:
30 words ending with ac, 12 letters long

ablutomaniac aboulomaniac agoraphobiac anglophobiac bibliomaniac bradycardiac cleptomaniac coprophiliac cyclothymiac demonomaniac diplocardiac etheromaniac extracardiac haemophiliac hebephreniac intracardiac kleptomaniac megalomaniac melancholiac necrophiliac negrophobiac nymphomaniac ochlophobiac paedophiliac retrophiliac russophobiac scopophiliac tachycardiac technomaniac timbromaniac