12 letter words:
nonpoisonous14,
9 letter words:
poisonous11,
8 letter words:
opsonins10,
sponsion10,
7 letter words:
opsonin9,
poisons9,
spinous9,
sponson9,
unisons7,
6 letter words:
opsins8,
pinons8,
poison8,
snoops8,
spoons8,
unpins8,
ninons6,
onions6,
unions6,
unison6,
5 letter words:
opsin7,
pinon7,
pions7,
pious7,
pisos7,
poons7,
snips7,
snoop7,
soups7,
spins7,
spoon7,
unpin7,
ninon5,
nisus5,
noons5,
nouns5,
onion5,
sinus5,
sunns5,
union5,
4 letter words:
nips6,
oops6,
opus6,
pins6,
pion6,
piso6,
piss6,
pois6,
pons6,
poon6,
poos6,
psis6,
puns6,
puss6,
sips6,
snip6,
sops6,
soup6,
spin6,
spun6,
sups6,
upon6,
inns4,
ions4,
noon4,
noun4,
nous4,
nuns4,
onos4,
onus4,
sins4,
sons4,
soon4,
sous4,
sunn4,
suns4,
3 letter words:
nip5,
ops5,
pin5,
pis5,
piu5,
poi5,
poo5,
psi5,
pun5,
pus5,
sip5,
sop5,
sup5,
upo5,
ups5,
inn3,
ins3,
ion3,
noo3,
nos3,
nun3,
nus3,
ono3,
ons3,
sin3,
sis3,
son3,
sos3,
sou3,
sun3,
uns3,
2 letter words:
op4,
pi4,
up4,
in2,
is2,
no2,
nu2,
oi2,
on2,
os2,
si2,
so2,
un2,
us2,