nipter inpter npiter pniter ipnter pinter nitper intper ntiper tniper itnper tinper nptier pntier ntpier tnpier ptnier tpnier iptner pitner itpner tipner ptiner tpiner nipetr inpetr npietr pnietr ipnetr pinetr nieptr ineptr neiptr eniptr ienptr einptr npeitr pneitr nepitr enpitr penitr epnitr ipentr pientr iepntr eipntr peintr epintr nitepr intepr ntiepr tniepr itnepr tinepr nietpr inetpr neitpr enitpr ientpr eintpr nteipr tneipr netipr entipr tenipr etnipr itenpr tienpr ietnpr eitnpr teinpr etinpr npteir pnteir ntpeir tnpeir ptneir tpneir npetir pnetir neptir enptir pentir epntir ntepir tnepir netpir entpir tenpir etnpir ptenir tpenir petnir eptnir tepnir etpnir iptenr pitenr itpenr tipenr ptienr tpienr ipetnr pietnr ieptnr eiptnr peitnr epitnr itepnr tiepnr ietpnr eitpnr teipnr etipnr pteinr tpeinr petinr eptinr tepinr etpinr niptre inptre npitre pnitre ipntre pintre nitpre intpre ntipre tnipre itnpre tinpre nptire pntire ntpire tnpire ptnire tpnire iptnre pitnre itpnre tipnre ptinre tpinre niprte inprte npirte pnirte ipnrte pinrte nirpte inrpte nripte rnipte irnpte rinpte nprite pnrite nrpite rnpite prnite rpnite iprnte pirnte irpnte ripnte printe rpinte nitrpe intrpe ntirpe tnirpe itnrpe tinrpe nirtpe inrtpe nritpe rnitpe irntpe rintpe ntripe tnripe nrtipe rntipe trnipe rtnipe itrnpe tirnpe irtnpe ritnpe trinpe rtinpe nptrie pntrie ntprie tnprie ptnrie tpnrie nprtie pnrtie nrptie rnptie prntie rpntie ntrpie tnrpie nrtpie rntpie trnpie rtnpie ptrnie tprnie prtnie rptnie trpnie rtpnie iptrne pitrne itprne tiprne ptirne tpirne iprtne pirtne irptne riptne pritne rpitne itrpne tirpne irtpne ritpne tripne rtipne ptrine tprine prtine rptine trpine rtpine nipert inpert npiert pniert ipnert pinert nieprt ineprt neiprt eniprt ienprt einprt npeirt pneirt nepirt enpirt penirt epnirt ipenrt pienrt iepnrt eipnrt peinrt epinrt nipret inpret npiret pniret ipnret pinret nirpet inrpet nripet rnipet irnpet rinpet npriet pnriet nrpiet rnpiet prniet rpniet iprnet pirnet irpnet ripnet prinet rpinet nierpt inerpt neirpt enirpt ienrpt einrpt nirept inrept nriept rniept irnept rinept neript enript nreipt rneipt ernipt renipt iernpt eirnpt irenpt rienpt erinpt reinpt nperit pnerit neprit enprit penrit epnrit npreit pnreit nrpeit rnpeit prneit rpneit nerpit enrpit nrepit rnepit ernpit renpit pernit eprnit prenit rpenit erpnit repnit ipernt piernt ieprnt eiprnt peirnt epirnt iprent pirent irpent ripent prient rpient ierpnt eirpnt irepnt riepnt eripnt reipnt perint eprint preint rpeint erpint repint niterp interp ntierp tnierp itnerp tinerp nietrp inetrp neitrp enitrp ientrp eintrp nteirp tneirp netirp entirp tenirp etnirp itenrp tienrp ietnrp eitnrp teinrp etinrp nitrep intrep ntirep tnirep itnrep tinrep nirtep inrtep nritep rnitep irntep rintep ntriep tnriep nrtiep rntiep trniep rtniep itrnep tirnep irtnep ritnep trinep rtinep niertp inertp neirtp enirtp ienrtp einrtp niretp inretp nrietp rnietp irnetp rinetp neritp enritp nreitp rneitp ernitp renitp ierntp eirntp irentp rientp erintp reintp nterip tnerip netrip entrip tenrip etnrip ntreip tnreip nrteip rnteip trneip rtneip nertip enrtip nretip rnetip erntip rentip ternip etrnip trenip rtenip ertnip retnip iternp tiernp ietrnp eitrnp teirnp etirnp itrenp tirenp irtenp ritenp trienp rtienp iertnp eirtnp iretnp rietnp eritnp reitnp terinp etrinp treinp rteinp ertinp retinp npteri pnteri ntperi tnperi ptneri tpneri npetri pnetri neptri enptri pentri epntri ntepri tnepri netpri entpri tenpri etnpri ptenri tpenri petnri eptnri tepnri etpnri nptrei pntrei ntprei tnprei ptnrei tpnrei nprtei pnrtei nrptei rnptei prntei rpntei ntrpei tnrpei nrtpei rntpei trnpei rtnpei ptrnei tprnei prtnei rptnei trpnei rtpnei nperti pnerti neprti enprti penrti epnrti npreti pnreti nrpeti rnpeti prneti rpneti nerpti enrpti nrepti rnepti ernpti renpti pernti eprnti prenti rpenti erpnti repnti nterpi tnerpi netrpi entrpi tenrpi etnrpi ntrepi tnrepi nrtepi rntepi trnepi rtnepi nertpi enrtpi nretpi rnetpi erntpi rentpi ternpi etrnpi trenpi rtenpi ertnpi retnpi pterni tperni petrni eptrni teprni etprni ptreni tpreni prteni rpteni trpeni rtpeni pertni eprtni pretni rpetni erptni reptni terpni etrpni trepni rtepni ertpni retpni iptern pitern itpern tipern ptiern tpiern ipetrn pietrn ieptrn eiptrn peitrn epitrn iteprn tieprn ietprn eitprn teiprn etiprn pteirn tpeirn petirn eptirn tepirn etpirn iptren pitren itpren tipren ptiren tpiren iprten pirten irpten ripten priten rpiten itrpen tirpen irtpen ritpen tripen rtipen ptrien tprien prtien rptien trpien rtpien ipertn piertn ieprtn eiprtn peirtn epirtn ipretn piretn irpetn ripetn prietn rpietn ierptn eirptn ireptn rieptn eriptn reiptn peritn epritn preitn rpeitn erpitn repitn iterpn tierpn ietrpn eitrpn teirpn etirpn itrepn tirepn irtepn ritepn triepn rtiepn iertpn eirtpn iretpn rietpn eritpn reitpn teripn etripn treipn rteipn ertipn retipn pterin tperin petrin eptrin teprin etprin ptrein tprein prtein rptein trpein rtpein pertin eprtin pretin rpetin erptin reptin terpin etrpin trepin rtepin ertpin retpin
Note: these 'words' (valid or invalid) are all the permutations of the word nipter. These words are obtained by scrambling the letters in nipter.