Mammoth Uncensored Word List:
39 words ending with am, 10 letters long

brontogram cardiogram chromogram chronogram clonazepam cryptogram cunningham datastream dendrogram disulfiram downstream esophagram headstream intravitam lymphogram mainstream millstream misprogram nitrazepam nonprogram organogram phanerogam phlebogram pneumogram polarogram preprogram psychogram scintigram seismogram shadowgram sidestream siphonogam slipstream sphenogram stereogram stripagram subprogram tarmacadam thermogram