freon rfeon feron efron refon erfon froen rfoen foren ofren rofen orfen feorn eforn foern ofern eofrn oefrn reofn erofn roefn orefn eorfn oerfn freno rfeno ferno efrno refno erfno frneo rfneo fnreo nfreo rnfeo nrfeo fenro efnro fnero nfero enfro nefro renfo ernfo rnefo nrefo enrfo nerfo frone rfone forne ofrne rofne orfne frnoe rfnoe fnroe nfroe rnfoe nrfoe fonre ofnre fnore nfore onfre nofre ronfe ornfe rnofe nrofe onrfe norfe feonr efonr foenr ofenr eofnr oefnr fenor efnor fneor nfeor enfor nefor foner ofner fnoer nfoer onfer nofer eonfr oenfr enofr neofr onefr noefr reonf eronf roenf orenf eornf oernf renof ernof rneof nreof enrof nerof ronef ornef rnoef nroef onref noref eonrf oenrf enorf neorf onerf noerf
Note: these 'words' (valid or invalid) are all the permutations of the word freon. These words are obtained by scrambling the letters in freon.