Source : Webster's Revised Unabridged Dictionary (1913)

Quintet \Quin*tet"\, Quintette \Quin*tette"\, n. [It. quintetto,
   dim. of quinto the fifth, a fifth part, from L. quintus the
   fifth: cf. F. quintette. See {Quint}.] (Mus.)
   A composition for five voices or instruments; also, the set
   of five persons who sing or play five-part music.

Source : WordNet®

quintette
     n 1: five performers or singers who perform together [syn: {quintet}]
     2: a set of five similar things considered as a unit [syn: {quintet}]
     3: five people considered as a unit [syn: {quintet}, {fivesome}]
     4: a musical composition for five performers [syn: {quintet}]