Low form of night life (3)
I believe the answer is:
owl
'night life' is the definition.
The definition and answer can be both animals as well as being singular nouns.
Perhaps you can see an association between them that I can't see?
'low form' is the wordplay.
'form' indicates anagramming the letters (another form of the letters).
'low' is an anagram of 'OWL'.
'of' acts as a link.
Can you help me to learn more?
(Other definitions for owl that I've seen before include "Mainly nocturnal bird" , "Wise figure" , "eg Snowy, Tawny" , "Wise old night-flier" , "Pussy-cat's wooer (Lear)" .)