prestissimo

from WordNet (r) 3.0 (2006)

prestissimo
    adv 1: extremely fast; as fast as possible; "this passage should
           be played prestissimo"
    adj 1: (of tempo) as fast as possible

from The Collaborative International Dictionary of English v.0.48

Prestissimo \Pres*tis"si*mo\, adv. [It., superl. of presto.]
   (Mus.)
   Very quickly; with great rapidity.
   [1913 Webster]

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