Keep Your Hair On
What does it mean?
Quick summary: A common British phrase meaning calm down and do not get angry or overexcited.
Keep your hair on is a casual way of telling someone to relax, be patient, or stop getting worked up.
REAL ENGLISH.

Is it positive or negative?
It can sound neutral or slightly negative because it is often said when someone is annoyed.
When do you use it?
Use it in casual conversation when somebody is becoming impatient, snappy, or dramatic.
Examples
Example 1: Keep your hair on - I am nearly ready.
Example 2: She told him to keep his hair on and wait for the full story.
Question for you
When do people most need to be told to keep their hair on?
Try saying your answer aloud, using the expression.
Practise it in a lesson
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