also: じょうい
I put on a coat and went out because it was cold.
会議のときは上着を着用してください。
Please wear a jacket for the meeting.
top; upper-body garment
Refers to any garment worn on the upper body, contrasting with 下着 (underwear) or ズボン (trousers). Often used in clothing sets or laundry contexts.
このパジャマの上着は薄手で夏向きだ。
The top of these pajamas is thin and suitable for summer.
洗濯する前に上着と下着を分けてください。
Please separate the tops and underwear before washing.
It's cold, so please put on a jacket.
I took off my jacket before entering the room.
It was a bit chilly, so I threw on a jacket before going out.
I hung the jacket on a hanger.
上着 is the everyday word for a jacket or outer layer, while 外衣 is a more formal or literary term for the same idea.
Formal or technical reading, often used in clothing industry or uniform descriptions.
Rarely used kanji form.