Very friendly alien seen in copse (7)
I believe the answer is:
thicket
'copse' is the definition.
('thicket' can be a synonym of 'copse')
'very friendly alien' is the wordplay.
'very friendly' becomes 'thick' (I've seen this before. I am not sure about the 'very' bit.**).
'alien' becomes 'et' (extra terrestrial).
'thick'+'et'='THICKET'
'seen in' is the link.
Can you help me to learn more?
(Other definitions for thicket that I've seen before include "Copse" , "Dense mass of trees or shrubs" , "A patch of shrubs and small trees" , "Dense bushy area" , "dense vegetation" .)