uncap nucap ucnap cunap ncuap cnuap unacp nuacp uancp auncp naucp anucp ucanp cuanp uacnp aucnp caunp acunp ncaup cnaup nacup ancup canup acnup uncpa nucpa ucnpa cunpa ncupa cnupa unpca nupca upnca punca npuca pnuca ucpna cupna upcna pucna cpuna pcuna ncpua cnpua npcua pncua cpnua pcnua unapc nuapc uanpc aunpc naupc anupc unpac nupac upnac punac npuac pnuac uapnc aupnc upanc puanc apunc paunc napuc anpuc npauc pnauc apnuc panuc ucapn cuapn uacpn aucpn caupn acupn ucpan cupan upcan pucan cpuan pcuan uapcn aupcn upacn puacn apucn paucn capun acpun cpaun pcaun apcun pacun ncapu cnapu nacpu ancpu canpu acnpu ncpau cnpau npcau pncau cpnau pcnau napcu anpcu npacu pnacu apncu pancu capnu acpnu cpanu pcanu apcnu pacnu
Note: these 'words' (valid or invalid) are all the permutations of the word uncap. These words are obtained by scrambling the letters in uncap.