spitr psitr siptr isptr pistr ipstr sptir pstir stpir tspir ptsir tpsir sitpr istpr stipr tsipr itspr tispr pitsr iptsr ptisr tpisr itpsr tipsr spirt psirt siprt isprt pisrt ipsrt sprit psrit srpit rspit prsit rpsit sirpt isrpt sript rsipt irspt rispt pirst iprst prist rpist irpst ripst sptri pstri stpri tspri ptsri tpsri sprti psrti srpti rspti prsti rpsti strpi tsrpi srtpi rstpi trspi rtspi ptrsi tprsi prtsi rptsi trpsi rtpsi sitrp istrp stirp tsirp itsrp tisrp sirtp isrtp sritp rsitp irstp ristp strip tsrip srtip rstip trsip rtsip itrsp tirsp irtsp ritsp trisp rtisp pitrs iptrs ptirs tpirs itprs tiprs pirts iprts prits rpits irpts ripts ptris tpris prtis rptis trpis rtpis itrps tirps irtps ritps trips rtips
Note: these 'words' (valid or invalid) are all the permutations of the word spitr. These words are obtained by scrambling the letters in spitr.