Mammoth Uncensored Word List:
74 words ending with ps, 14 letters long

assistantships associateships barristerships brinksmanships candidateships chieftainships churchmanships coadjutorships colleagueships collectorships commanderships committeeships companionships conductorships confessorships constableships containerships copartnerships cosponsorships councilorships counselorships craftsmanships custodianships disfellowships draftsmanships gentlemanships gladiatorships grantsmanships homeownerships housewifeships housewifeskeps imperatorships indentureships inspectorships justiciarships landownerships librarianships moderatorships nonmemberships ombudsmanships pendragonships physicianships ploughmanships possessorships postulantships precentorships preceptorships presbyterships presidentships pretenderships principalships proconsulships professorships prosectorships protectorships registrarships rumbledethumps scrivenerships secretaryships seneschalships solicitorships spectatorships spokesmanships sportsmanships statesmanships subdeaconships subeditorships succentorships successorships suffraganships surrogateships swordsmanships treasurerships yachtsmanships