rin·for·zan·do 
(rēn′fôr-tsändō)
(rēn′fôr-tsändō)adv. & adj. Abbr. rf or rfz
Music
Music
With a sudden increase of emphasis. Used chiefly as a direction.
[Italian, present participle of rinforzare, to reinforce, strengthen : ri-, again (from Latin re-; see RE-) + inforzare, to enforce, make strong (from Old French enforcier; see ENFORCE).]