fecal efcal fceal cfeal ecfal cefal feacl efacl faecl afecl eafcl aefcl fcael cfael facel afcel cafel acfel ecafl ceafl eacfl aecfl caefl acefl fecla efcla fcela cfela ecfla cefla felca eflca fleca lfeca elfca lefca fclea cflea flcea lfcea clfea lcfea eclfa celfa elcfa lecfa clefa lcefa fealc efalc faelc afelc eaflc aeflc felac eflac fleac lfeac elfac lefac falec aflec flaec lfaec alfec lafec ealfc aelfc elafc leafc alefc laefc fcale cfale facle afcle cafle acfle fclae cflae flcae lfcae clfae lcfae falce aflce flace lface alfce lafce calfe aclfe clafe lcafe alcfe lacfe ecalf cealf eaclf aeclf caelf acelf eclaf celaf elcaf lecaf cleaf lceaf ealcf aelcf elacf leacf alecf laecf calef aclef claef lcaef alcef lacef
Note: these 'words' (valid or invalid) are all the permutations of the word fecal. These words are obtained by scrambling the letters in fecal.