Definitions of tough

1. 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.

2. Not easily broken; able to endure hardship; firm; strong; as, tough sinews.

3. Not easily separated; viscous; clammy; tenacious; as, tough phlegm.

4. Stiff; rigid; not flexible; stubborn; as, a tough bow.

5. Severe; violent; as, a tough storm.

6. a cruel and brutal fellow

7. someone who learned to fight in the streets rather than being formally trained in the sport of boxing

8. Colloquially, a rough fellow; a rowdy.

9. Toughness.

10. Toughly.

11. very difficult; severely testing stamina or resolution; " a rugged competitive examination"; " the rugged conditions of frontier life"; " the competition was tough"; " it's a tough life"; " it was a tough job"

12. unfortunate or hard to bear; " had hard luck"; " a tough break"

13. tough to cut or chew

14. feeling physical discomfort or pain (` tough' is occasionally used colloquially for ` bad'); " my throat feels bad"; " she felt bad all over"; " he was feeling tough after a restless night"

15. not given to gentleness or sentimentality; " a tough character"

16. Not easily broken: firm: stiff: sticky: tenacious: able to endure hardship.

17. Not easily broken; tenacious; strong; able to endure hardship.

18. Admitting of tugging and pulling without fracture or injury; not easily broken or separated; able to endure hardships; tenacious; difficult, as a tough piece of business.