English Etymology From poly- + ether + ketone + ether + ketone + ketone. Noun polyetherketoneetherketoneketone (uncountable) A thermoplastic polymer used in surgical implants. Synonym: PEKEKK Usage notes This is the english word with the most "E"s, 10 of them to be exact.Wikiwand - on Seamless Wikipedia browsing. On steroids.