Key change of price around end of month (6)
I believe the answer is:
cipher
'key change' is the definition.
The answer and definition can be both related to communication as well as being singular nouns.
Maybe they are linked in a way I don't understand?
'of price around end of month' is the wordplay.
'of' indicates anagramming the letters (the answer comes from or 'of' the letters).
'around end of' says to take the final letters.
The final letter of 'month' is 'h'.
'price'+'h'='priceh'
'priceh' is an anagram of 'CIPHER'.
Can you help me to learn more?
(Other definitions for cipher that I've seen before include "Person or thing of no importance, or the symbol 0" , "Symbol representing nought, thing of no importance" , "Code - 0" , "Secret code" , "Key to a code" .)