mstop smtop mtsop tmsop stmop tsmop msotp smotp mostp omstp somtp osmtp mtosp tmosp motsp omtsp tomsp otmsp stomp tsomp sotmp ostmp tosmp otsmp mstpo smtpo mtspo tmspo stmpo tsmpo mspto smpto mpsto pmsto spmto psmto mtpso tmpso mptso pmtso tpmso ptmso stpmo tspmo sptmo pstmo tpsmo ptsmo msopt smopt mospt omspt sompt osmpt mspot smpot mpsot pmsot spmot psmot mopst ompst mpost pmost opmst pomst sopmt ospmt spomt psomt opsmt posmt mtops tmops motps omtps tomps otmps mtpos tmpos mptos pmtos tpmos ptmos mopts ompts mpots pmots opmts pomts topms otpms tpoms ptoms optms potms stopm tsopm sotpm ostpm tospm otspm stpom tspom sptom pstom tpsom ptsom soptm osptm spotm psotm opstm postm topsm otpsm tposm ptosm optsm potsm
Note: these 'words' (valid or invalid) are all the permutations of the word mstop. These words are obtained by scrambling the letters in mstop.