Cursing having no dogs is no good (3)
I believe the answer is:
sin
'cursing having' is the definition.
I can't judge whether this definition defines the answer.
'no dogs is no good' is the wordplay.
'no' becomes 'n' (common abbreviation).
'dogs' means one lot of letters go next to another (dogs can mean follows or chases).
'no good' is an anagram indicator (no good can mean faulty or defective).
'is' is an anagram of 'si'.
'n' after 'si' is 'SIN'.
Can you help me to learn more?
(Other definitions for sin that I've seen before include "Breach of moral code" , "Serious transgression" , "Go astray" , "grave offence" , "Wickedness" .)