1) Abruptly 2) Against the grain 3) Bitterly 4) Brusquely 5) Cruelly 6) Dissonantly 7) Dourly 8) Gratingly 9) Nastily 10) Piercingly 11) Raspingly 12) Roughly 13) Severely 14) Sharply 15) Sourly 16) Strictly 17) Unkindly 1) Brutally 2) Coarsely 3) Cruelly 4) Gratingly 5) In a harsh and grating manner 6) In a harsh or unkind manner 7) In a stern way 8) In an unkind way 9) In unkind style 10) Raspingly 11) Relentlessly 12) Rigorously 13) Roughly 14) Ruthlessly 15) Scratchily 16) Sternly 17) Strictly 18) Stridently 19) Without mercy 
• (adv.) In a harsh manner; gratingly; roughly; rudely.
Harsh'ly adverb In a harsh manner; gratingly; roughly; rudely. « 'T will sound harshly in her ears.» Shak. 
[adv] - in a harsh or unkind manner