·superl Severe; violent; as, a tough storm.
II. Tough ·superl Stiff; rigid; not flexible; stubborn; as, a tough bow.
III. Tough ·superl Not easily separated; viscous; clammy; tenacious; as, tough phlegm.
IV. Tough ·superl Not easily broken; able to endure hardship; firm; strong; as, tough sinews.
V. Tough ·superl Having the quality of flexibility without brittleness; yielding to force without breaking; capable of resisting great strain; as, the ligaments of animals are remarkably tough.