Talk down to
Definition 1 of 1
Pro Tip 1/3Power Dynamics
Used when someone asserts superiority in knowledge or status over another person. 
Her manager would often talk down to her, making her feel undervalued.
Pro Tip 2/3Disrespectful Tone
The phrase often implies a disrespectful or belittling tone. 
I disliked how he would talk down to the interns, as if they couldn’t understand simple instructions.
Pro Tip 3/3Emotional Impact
Being talked down to can make the listener feel inferior or disrespected. 
She felt demoralized when her tutor talked down to her for making a mistake.