To blend in is to fit so well with the surroundings that nobody notices you. Try to blend in.
It is about behaviour more than appearance, since standing still and looking about is what gives people away. To blend in is what every traveller wanting to avoid attention actually needs.
1phraseblend inTo fit so well with the surroundings that nobody notices you.
“He could blend in anywhere by walking as though he knew the way.”
blend in is a phrase.
Practised in Phrasal Verbs