1. 
[syn: rallentando, ritardando, ritenuto, rit.]
ADVERB (1)
1.  slowing down; 
- Example: "this passage should be played rallentando"
The Collaborative International Dictionary of English v.0.48:
Rallentando \Ral`len*tan"do\ (r[aum]l`l[e^]n*t[aum]n"d[-o]), a.
   [It.] (Mus.)
   Slackening; -- a direction to perform a passage with a
   gradual decrease in time and force; ritardando.
   [1913 Webster]
WordNet (r) 3.0 (2006):
rallentando
    adv 1: slowing down; "this passage should be played rallentando"
    adj 1: gradually decreasing in tempo [syn: rallentando,
           ritardando, ritenuto, rit.]