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Webster 1913 Edition
Serenate
{ 
Serˊe-na′ta
,Ser′e-nate
, }Noun.
 [It. 
serenata
. See Serenade
.] (Mus.) 
A piece of vocal music, especially one on an amoreus subject; a serenade. 
Or 
To his pround fair.
serenate
, which the starved lover singsTo his pround fair.
Milton.
☞ The name serenata was given by Italian composers in the time of Handel, and by Handel himself, to a cantata of a pastoreal of dramatic character, to a secular ode, etc.; also by Mozart and others to an orchectral composition, in several movements, midway between the suite of an earlier period and the modern symphony. 
Grove.