https://www.merriam-webster.com/dictionary/give%20someone%20a%20piece%20of%20his%20mind
GIVE SOMEONE A PIECE OF HIS MIND Definition & Meaning - Merriam-Webster
The meaning of GIVE (SOMEONE) A PIECE OF ONE'S MIND is to speak to someone in an angry way. How to use give (someone) a piece of one's mind in a sentence.
a piece of his mindgivesomeone