[1] : The Collaborative International Dictionary of English v.0.48

appoggiatura \appog`giatu"ra\, n. it., fr. appogiarre to
   lean, to rest; ap- l. ad + poggiare to mount, ascend,
   poggio hill, fr. l. podium an elevated place. mus.
   a passing tone preceding an essential tone, and borrowing the
   time it occupies from that; a short auxiliary or grace note
   one degree above or below the principal note unless it be of
   the same harmony; -- generally indicated by a note of smaller
   size, as in the illustration above. it forms no essential
   part of the harmony.
   1913 webster

[2] : WordNet (r) 2.0

appoggiatura
     n : an embellishing note usually written in smaller size syn: grace
         note, acciaccatura
     also: appoggiature pl
see also:
grace note acciaccatura appoggiature 

Appoggiatura >> A Words
Appoggiatura, definition of term: Appoggiatura
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