Definitions by UrsaLinguistics

lower your voice 

When someone is being offensive (and/or in a state of anger) and shouts at you you respond with "lower your voice" to tell them you're not alright with their attitude and conversation manner.

Kid: Stop talking about school and grades, Mom! (shouting or speaking loudly)
Mom: Lower your voice!

lower your voice by UrsaLinguistics August 4, 2014