High explosives trade corrupt and underground (7)
I believe the answer is:
earthed
'underground' is the definition.
The answer and definition are different parts of speech. However, adjectives and past participle verbs sometimes mean the same thing.
'high explosives trade corrupt' is the wordplay.
I cannot really see how this works, but
'high' could be 'h' (abbreviation) and 'h' is found in the answer.
an anagram of 'trade' is 'arted' which is within the remaining letters.
A single letter 'e' remains which might be clued in a way I don't understand.
This explanation may well be incorrect...
'and' is the link.
Can you help me to learn more?
(Other definitions for earthed that I've seen before include "protected from shock" , "attached to the ground" , "grounded" .)