Group half the size of a sextet (4)
I believe the answer is:
trio
(Other definitions for trio that I've seen before include "Threesome" , "Three together" , "father, spirit and son" , "Three of a kind" , "(Composition for) three performers" .)
I believe the answer is:
trio
(Other definitions for trio that I've seen before include "Threesome" , "Three together" , "father, spirit and son" , "Three of a kind" , "(Composition for) three performers" .)