Definition that contains tractile
- muscle one of the contractile organs of the body
- muscle animal tissue consisting predominantly of contractile cells
- pupil the contractile aperture in the center of the iris of the eye; resembles a large black dot
- cheetah long-legged spotted cat of Africa and southwestern Asia having nonretractile claws; the swiftest mammal; can be trained to run down game
- canine any of various fissiped mammals with nonretractile claws and typically long muzzles
- feline any of various lithe-bodied roundheaded fissiped mammals, many with retractile claws
- canid any of various fissiped mammals with nonretractile claws and typically long muzzles
- sarcostyle one of many contractile filaments that make up a striated muscle fiber
- genus vorticella ciliated protozoans that have a goblet-shaped body with a retractile stalk
- tentaculata ctenophores have retractile tentacles