bifid ibfid bfiid fbiid ifbid fibid biifd ibifd biifd ibifd iibfd iibfd bfiid fbiid bifid ibfid fibid ifbid ifibd fiibd iifbd iifbd fiibd ifibd bifdi ibfdi bfidi fbidi ifbdi fibdi bidfi ibdfi bdifi dbifi idbfi dibfi bfdii fbdii bdfii dbfii fdbii dfbii ifdbi fidbi idfbi difbi fdibi dfibi biidf ibidf biidf ibidf iibdf iibdf bidif ibdif bdiif dbiif idbif dibif bidif ibdif bdiif dbiif idbif dibif iidbf iidbf idibf diibf idibf diibf bfidi fbidi bifdi ibfdi fibdi ifbdi bfdii fbdii bdfii dbfii fdbii dfbii bidfi ibdfi bdifi dbifi idbfi dibfi fidbi ifdbi fdibi dfibi idfbi difbi ifidb fiidb iifdb iifdb fiidb ifidb ifdib fidib idfib difib fdiib dfiib iidfb iidfb idifb diifb idifb diifb fidib ifdib fdiib dfiib idfib difib
Note: these 'words' (valid or invalid) are all the permutations of the word bifid. These words are obtained by scrambling the letters in bifid.