Chilopoda
Chordata
Echiuroidea
Ectoprocta
Entoprocta
Milquetoast
Monoplacophora
Nemertinea
Phoronidea
baby
big baby
chicken
chicken liver
coward
crybaby
doormat
dull tool
fence-sitter
fraid-cat
fraidy-cat
funk
funker
gutless wonder
invertebrate
lightweight
lily liver
meek soul
milksop
mollycoddle
mouse
mugwump
namby-pamby
nebbish
nonentity
pansy
pantywaist
pushover
sad sack
scaredy-cat
shilly-shally
sissy
softling
softy
sop
waverer
weak sister
weakling
white feather
white liver
wobbler
Medusa
acaleph
jellyfishes
siphonophore
abalone
algae
anemone
mussel
octopi
octopus
plankton
porpoise
prawn
shrimp
squid
stormtrooper