opter poter otper toper ptoer tpoer opetr poetr oeptr eoptr peotr epotr otepr toepr oetpr eotpr teopr etopr pteor tpeor petor eptor tepor etpor optre potre otpre topre ptore tpore oprte porte orpte ropte prote rpote otrpe torpe ortpe rotpe trope rtope ptroe tproe prtoe rptoe trpoe rtpoe opert poert oeprt eoprt peort eport opret poret orpet ropet proet rpoet oerpt eorpt orept roept eropt reopt perot eprot preot rpeot erpot repot oterp toerp oetrp eotrp teorp etorp otrep torep ortep rotep troep rtoep oertp eortp oretp roetp erotp reotp terop etrop treop rteop ertop retop ptero tpero petro eptro tepro etpro ptreo tpreo prteo rpteo trpeo rtpeo perto eprto preto rpeto erpto repto terpo etrpo trepo rtepo ertpo retpo
Note: these 'words' (valid or invalid) are all the permutations of the word opter. These words are obtained by scrambling the letters in opter.