Sometimes; It depends on the context. When you use the word "harder" as for difficulty level, then yes, tougher is a synonym for harder. If you are talking about the firmness of an object, tougher is NOT a synonym for harder. Or if you're talking about the chewyness of something.
stronger, harder, rougher, more dangerous.
Another word is but
another word for very large
tougher
Suggestion is another word for proposal answer: engagement?
stronger, harder, rougher, more dangerous.
Try harder can be the other way to replace work harder, too.
They become tougher.
Wisconsin, but Iowa is tougher yet.
Any species of Oak is stronger than any species of Aspen. Aspen is among the weakest and softest of woods. Some Oaks are harder and tougher than others, but all species of Oak are harder and tougher - not to mention a lot heavier - than any species of Aspen.
It becomes harder and tougher. Manganese steel is what soldiers helmets were made out of in WW II.
In what context: harder as in metals, or harder as in difficult?
The opposite of "easier" is "harder."
always get harder
I'd like another title example, please. This title is becoming harder to locate.
The more gym leaders u go to the harder and longer it will be cause the challengers and the puzzle get tougher so sometimes yes and sometimes no.
Hard