Evil deed by goblin was obstructive (7)
I believe the answer is:
impeded
'obstructive' is the definition.
The answer and definition are not the same part of speech. However, past participle verbs and adjectives can sometimes define each other.
'evil deed by goblin' is the wordplay.
'evil' indicates anagramming the letters.
'by' means one lot of letters go next to another.
'goblin' becomes 'imp' (I've seen this before).
'deed' with letters rearranged gives 'eded'.
'eded' after 'imp' is 'IMPEDED'.
'was' acts as a link.
Can you help me to learn more?
(Other definitions for impeded that I've seen before include "Held up" , "Hampered" , "Blocked, hindered" , "Blocked (progress)" , "Got in the way of" .)