ursids rusids usrids surids rsuids sruids urisds ruisds uirsds iursds riusds irusds usirds suirds uisrds iusrds siurds isurds rsiuds sriuds risuds irsuds siruds isruds ursdis rusdis usrdis surdis rsudis srudis urdsis rudsis udrsis dursis rdusis drusis usdris sudris udsris dusris sduris dsuris rsduis srduis rdsuis drsuis sdruis dsruis uridss ruidss uirdss iurdss riudss irudss urdiss rudiss udriss duriss rduiss druiss uidrss iudrss udirss duirss idurss diurss riduss irduss rdiuss driuss idruss diruss usidrs suidrs uisdrs iusdrs siudrs isudrs usdirs sudirs udsirs dusirs sduirs dsuirs uidsrs iudsrs udisrs duisrs idusrs diusrs sidurs isdurs sdiurs dsiurs idsurs disurs rsidus sridus risdus irsdus sirdus isrdus rsdius srdius rdsius drsius sdrius dsrius ridsus irdsus rdisus drisus idrsus dirsus sidrus isdrus sdirus dsirus idsrus disrus ursisd rusisd usrisd surisd rsuisd sruisd urissd ruissd uirssd iurssd riussd irussd usirsd suirsd uisrsd iusrsd siursd isursd rsiusd sriusd risusd irsusd sirusd isrusd urssid russid usrsid sursid rsusid srusid urssid russid usrsid sursid rsusid srusid ussrid susrid ussrid susrid ssurid ssurid rssuid srsuid rssuid srsuid ssruid ssruid urissd ruissd uirssd iurssd riussd irussd ursisd rusisd usrisd surisd rsuisd sruisd uisrsd iusrsd usirsd suirsd isursd siursd risusd irsusd rsiusd sriusd isrusd sirusd usisrd suisrd uissrd iussrd siusrd isusrd ussird susird ussird susird ssuird ssuird uissrd iussrd usisrd suisrd isusrd siusrd sisurd issurd ssiurd ssiurd issurd sisurd rsisud srisud rissud irssud sirsud isrsud rssiud srsiud rssiud srsiud ssriud ssriud rissud irssud rsisud srisud isrsud sirsud sisrud issrud ssirud ssirud issrud sisrud ursdsi rusdsi usrdsi surdsi rsudsi srudsi urdssi rudssi udrssi durssi rdussi drussi usdrsi sudrsi udsrsi dusrsi sdursi dsursi rsdusi srdusi rdsusi drsusi sdrusi dsrusi urssdi russdi usrsdi sursdi rsusdi srusdi urssdi russdi usrsdi sursdi rsusdi srusdi ussrdi susrdi ussrdi susrdi ssurdi ssurdi rssudi srsudi rssudi srsudi ssrudi ssrudi urdssi rudssi udrssi durssi rdussi drussi ursdsi rusdsi usrdsi surdsi rsudsi srudsi udsrsi dusrsi usdrsi sudrsi dsursi sdursi rdsusi drsusi rsdusi srdusi dsrusi sdrusi usdsri sudsri udssri dussri sdusri dsusri ussdri susdri ussdri susdri ssudri ssudri udssri dussri usdsri sudsri dsusri sdusri sdsuri dssuri ssduri ssduri dssuri sdsuri rsdsui srdsui rdssui drssui sdrsui dsrsui rssdui srsdui rssdui srsdui ssrdui ssrdui rdssui drssui rsdsui srdsui dsrsui sdrsui sdsrui dssrui ssdrui ssdrui dssrui sdsrui uridss ruidss uirdss iurdss riudss irudss urdiss rudiss udriss duriss rduiss druiss uidrss iudrss udirss duirss idurss diurss riduss irduss rdiuss driuss idruss diruss urisds ruisds uirsds iursds riusds irusds ursids rusids usrids surids rsuids sruids uisrds iusrds usirds suirds isurds siurds risuds irsuds rsiuds sriuds isruds siruds urdsis rudsis udrsis dursis rdusis drusis ursdis rusdis usrdis surdis rsudis srudis udsris dusris usdris sudris dsuris sduris rdsuis drsuis rsduis srduis dsruis sdruis uidsrs iudsrs udisrs duisrs idusrs diusrs uisdrs iusdrs usidrs suidrs isudrs siudrs udsirs dusirs usdirs sudirs dsuirs sduirs idsurs disurs isdurs sidurs dsiurs sdiurs ridsus irdsus rdisus drisus idrsus dirsus risdus irsdus rsidus sridus isrdus sirdus rdsius drsius rsdius srdius dsrius sdrius idsrus disrus isdrus sidrus dsirus sdirus usidsr suidsr uisdsr iusdsr siudsr isudsr usdisr sudisr udsisr dusisr sduisr dsuisr uidssr iudssr udissr duissr idussr diussr sidusr isdusr sdiusr dsiusr idsusr disusr usisdr suisdr uissdr iussdr siusdr isusdr ussidr susidr ussidr susidr ssuidr ssuidr uissdr iussdr usisdr suisdr isusdr siusdr sisudr issudr ssiudr ssiudr issudr sisudr usdsir sudsir udssir dussir sdusir dsusir ussdir susdir ussdir susdir ssudir ssudir udssir dussir usdsir sudsir dsusir sdusir sdsuir dssuir ssduir ssduir dssuir sdsuir uidssr iudssr udissr duissr idussr diussr uisdsr iusdsr usidsr suidsr isudsr siudsr udsisr dusisr usdisr sudisr dsuisr sduisr idsusr disusr isdusr sidusr dsiusr sdiusr sidsur isdsur sdisur dsisur idssur dissur sisdur issdur ssidur ssidur issdur sisdur sdsiur dssiur ssdiur ssdiur dssiur sdsiur idssur dissur isdsur sidsur dsisur sdisur rsidsu sridsu risdsu irsdsu sirdsu isrdsu rsdisu srdisu rdsisu drsisu sdrisu dsrisu ridssu irdssu rdissu drissu idrssu dirssu sidrsu isdrsu sdirsu dsirsu idsrsu disrsu rsisdu srisdu rissdu irssdu sirsdu isrsdu rssidu srsidu rssidu srsidu ssridu ssridu rissdu irssdu rsisdu srisdu isrsdu sirsdu sisrdu issrdu ssirdu ssirdu issrdu sisrdu rsdsiu srdsiu rdssiu drssiu sdrsiu dsrsiu rssdiu srsdiu rssdiu srsdiu ssrdiu ssrdiu rdssiu drssiu rsdsiu srdsiu dsrsiu sdrsiu sdsriu dssriu ssdriu ssdriu dssriu sdsriu ridssu irdssu rdissu drissu idrssu dirssu risdsu irsdsu rsidsu sridsu isrdsu sirdsu rdsisu drsisu rsdisu srdisu dsrisu sdrisu idsrsu disrsu isdrsu sidrsu dsirsu sdirsu sidsru isdsru sdisru dsisru idssru dissru sisdru issdru ssidru ssidru issdru sisdru sdsiru dssiru ssdiru ssdiru dssiru sdsiru idssru dissru isdsru sidsru dsisru sdisru
Note: these 'words' (valid or invalid) are all the permutations of the word ursids. These words are obtained by scrambling the letters in ursids.