7 letter words:
ruffing14,
5 letter words:
griff12,
gruff12,
fungi9,
ruing6,
unrig6,
4 letter words:
guff11,
riff10,
ruff10,
frig8,
frug8,
firn7,
girn5,
grin5,
ring5,
rung5,
ruin4,
3 letter words:
iff9,
fig7,
fug7,
fin6,
fir6,
fun6,
fur6,
rif6,
gin4,
gnu4,
gun4,
rig4,
rug4,
rin3,
run3,
urn3,
2 letter words:
if5,
in2,
nu2,
un2,