Her home is the earth (5)
I believe the answer is:
vixen
'the earth' is the definition.
Although both the answer and definition are singular nouns, I can't see how one could define the other.
'her home' is the wordplay.
I cannot really see how this works, but
'her' could be 'vi' and 'vi' is found in the answer.
This may be the basis of the clue (or it may be nonsense).
'is' acts as a link.
Can you help me to learn more?
(Other definitions for vixen that I've seen before include "Female with a brush" , "Female fox - spiteful woman" , "Rudolph's partner" , "Bad-tempered woman - earth mother?" , "Cunning Little creature (Janacek)" .)