The correct way to install a jacket cuff suit is to only button the top button, so that the bottom of the jacket is open, revealing the belt or clothes inside. Don't wear anything greasy under a tight jacket. It's best to wear a tight T-shirt or a slimming pullover. Jacket is a transliteration of English Jacket. Jacket, coat. The earliest (about14th century) refers to waist-length, long sleeve, cardigan or pullover coat, which can be a single piece or a suit. With the development of the times, now, this word refers to all kinds of fabrics and styles, short coats and casual coats for various purposes.