Equipment mostly with current ground worker (4)
I believe the answer is:
kiwi
'worker' is the definition.
The answer and definition can be both animals as well as being singular nouns.
Perhaps there's an association between them I don't understand?
I don't understand how the rest of the clue works.
Can you help me to learn more?
(Other definitions for kiwi that I've seen before include "New Zealander's bird" , "Symbol of New Zealand" , "Flightless New Zealand bird" , "Rutherford was one" , "apteryx" .)