Copper’s timid and not dangerous (5)
I believe the answer is:
cushy
'not dangerous' is the definition.
(cushy means easy or untaxing)
'copper's timid' is the wordplay.
'copper' becomes 'cu' (chemical symbol).
'timid' becomes 'shy' (synonyms).
'cu'+'shy'='CUSHY'
'and' acts as a link.
(Other definitions for cushy that I've seen before include "Undemanding, secure" , "Simple" , "Undemanding, easy" , "16 21 [INDIAN IMPORT]" , "(Of situation) secure, easy (colloq.)" .)