Very friendly extra-terrestrial in copse (7)

I believe the answer is:

thicket

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'copse' is the definition.
(synonyms)

'very friendly extra-terrestrial' is the wordplay.
'very friendly' becomes 'thick' (I've seen this before. I am not sure about the 'very' bit.).
'extra terrestrial' becomes 'et' (abbreviation - like in the famous t98h movie).
'thick'+'et'='THICKET'

'in' is the link.

Can you help me to learn more?

(Other definitions for thicket that I've seen before include "Dense group of trees or bushes" , "Mass of shrubs and small trees growing close together" , "Coppice" , "dense vegetation" , "close gathering of elders?" .)

I've seen this clue in The Times.

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