I can't mess around with the meanings of words (9)
I believe the answer is:
semantics
'meanings of words' is the definition.
Although both the answer and definition are singular nouns, I don't understand how they can define each other.
'i can't mess around' is the wordplay.
'around' indicates anagramming the letters.
'i'+'cant'+'mess'='icantmess'
'icantmess' is an anagram of 'SEMANTICS'.
'with the' is the link.
Can you help me to learn more?
(Other definitions for semantics that I've seen before include "Branch of linguistics to do with meaning" , "The meaning attached to words" , "Main sects (anag.)" , "Meaning to study" , "Branch of linguistics concerned with meanings" .)