spinless
Without a spine
Spinless describes something lacking a spine—either literally, as with invertebrates, or figuratively, as with someone who lacks courage or conviction.
In physics, spinless refers to particles with zero spin, a quantum mechanical property: a spinless boson.
The figurative sense overlaps with spineless, though spineless is far more common for describing cowardice.
Lacking power or force
- cowardlyWithout bravery or nerve
- gutlessLacking bravery or nerve
- timidLacking courage or confidence
- irresoluteLacking firmness of purpose
feeble · wishy-washy · meek · pushover · doormat · submissive · backbone · courage
weak
Lacking power or force
irresolute · feeble · wishy-washy · meek · pushover · doormat · submissive · backbone · courage · fortitude
fermion
Half-integer spin particle
- bosonInteger-spin subatomic particle
- particleMinute piece of matter
- scalarQuantity with magnitude only
quantum · meson · pion · Higgs · field · intrinsic · angular momentum · hadron · baryon · photon
jellyfish
Drifting marine stinger
squid · snail · leech · flatworm · amoeba · sea cucumber · starfish · mollusk · cnidarian · soft-bodied