stoid tsoid sotid ostid tosid otsid stiod tsiod sitod istod tisod itsod soitd ositd siotd isotd oistd iostd toisd otisd tiosd itosd oitsd iotsd stodi tsodi sotdi ostdi tosdi otsdi stdoi tsdoi sdtoi dstoi tdsoi dtsoi sodti osdti sdoti dsoti odsti dosti todsi otdsi tdosi dtosi odtsi dotsi stido tsido sitdo istdo tisdo itsdo stdio tsdio sdtio dstio tdsio dtsio sidto isdto sdito dsito idsto disto tidso itdso tdiso dtiso idtso ditso soidt osidt siodt isodt oisdt iosdt sodit osdit sdoit dsoit odsit dosit sidot isdot sdiot dsiot idsot disot oidst iodst odist doist idost diost toids otids tiods itods oitds iotds todis otdis tdois dtois odtis dotis tidos itdos tdios dtios idtos ditos oidts iodts odits doits idots diots
Note: these 'words' (valid or invalid) are all the permutations of the word stoid. These words are obtained by scrambling the letters in stoid.