Speak harshly of something coarse of its kind (4)
I believe the answer is:
rasp
'speak harshly' is the definition.
(I've seen this in another clue)
I don't understand the rest of the clue.
Can you help me to learn more?
(Other definitions for rasp that I've seen before include "Harsh noise - file" , "Grate; scrape" , "Smoother" , "Filing tool" , "Abrade" .)