Not a good cottage perhaps for group of eight (5)

I believe the answer is:

octet

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'group of eight' is the definition.
(I've seen this before)

I don't understand how the rest of the clue works.

(Other definitions for octet that I've seen before include "Eight people together" , "music group" , "Group of eight players" , "Set of eight" , "Eightsome" .)

I've seen this clue in The Hindu.

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