(a) yavaş yavaş yıpratmak/yıpranmak/aşın(dır)mak.
He finished the wood by rubbing until he wore the surface down/ until the surface wore down. (b) zayıfla(t)mak, yor(ul)mak, kuvvetten düş(ür)mek.
The illness wore her down. (c) yenmek, dize getirmek, üstün gelmek, pes dedirmek.
To wear down the opposition.