A crab's in beetle-like form (6)
I believe the answer is:
scarab
'form' is the definition.
Although both the answer and definition are singular nouns, I don't see how one could define the other.
'a crab's in beetle-like' is the wordplay.
'a crab's' anagrams to 'SCARAB'.
But, I'm not clear how the anagram is indicated.
Can you help me to learn more?
(Other definitions for scarab that I've seen before include "Sacred dung-beetle" , "Large dark beetle" , "Ancient Egyptian symbol" , "Sacred beetle of Eygpt" , "Type of beetle" .)