Do One
What does it mean?
Quick summary: A blunt British slang phrase telling someone to go away.
Do one is a blunt, informal British way of telling someone to go away — sharper and less playful than 'jog on'.
REAL ENGLISH.

Is it positive or negative?
Negative. It's dismissive and can come across as rude depending on tone.
When do you use it?
Use it (carefully) to tell someone forcefully to leave you alone — mostly among close friends, otherwise it can sound properly rude.
Examples
Example 1: He wouldn't stop pestering me, so I told him to do one.
Example 2: "Lend us a tenner?" "Do one."
Question for you
Is there a phrase in your language as blunt as 'do one'?
Try saying your answer aloud, using the expression.
Practise it in a lesson
Know When to Be Direct in English (and When Not To)
Knowing exactly how blunt a phrase like this really sounds takes real cultural context — that's where a British native speaker helps. My online English lessons cover tone as well as vocabulary. Book a lesson here.
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