underwear, licentious, filthy

褻 is composed of 衣 (clothing) and 埶 (plant). 埶 is a pictograph of a person planting vegetation and carries the sense of touching. Therefore, 褻 conveys the idea of clothing worn close to the body, and means undergarments. Undergarments cling tightly to the body, easily become dirty, and should not be seen by outsiders. From this, 褻 extended to the meanings of casualness and uncleanliness.