6 letter words:
ferrum11,
5 letter words:
femur10,
fumer10,
freer8,
frere8,
refer8,
merer7,
murre7,
4 letter words:
feme9,
fume9,
fere7,
free7,
reef7,
emeu6,
mere6,
mure6,
murr6,
ruer4,
3 letter words:
fem8,
fee6,
fer6,
feu6,
fur6,
ref6,
eme5,
emu5,
rem5,
rum5,
ere3,
err3,
ree3,
rue3,
2 letter words:
ef5,
fe5,
em4,
me4,
mu4,
um4,
er2,
re2,