Etymology 1828, from French blouse (“a workman's or peasant's smock”), see that for more. More at blee, fold.
1
Fashion, LifestyleObsolete A shirt, typically loose and reaching from the neck to the waist.
2
Fashion, Lifestyle A shirt for women or girls, particularly a shirt with buttons and often a collar; a dress shirt tailored for women.
She came in now, but to the closet; from it she took a simple skirt and blouse. Picking up her underclothing she departed, obviously to dress somewhere else.1964, Philip K. Dick, “NINE”, in Clans of the Alphane Moon, United States: Ace Books, →OCLC; republished London: HarperCollinsPublishers, 1996, →ISBN, page 112:
An anonymous black soldier summed up his feelings by declaring, "If I fail to blouse my boots, or [if I] wear an Afro, I get socked. […]"1989, Bernard C. Nalty, Strength for the Fight: A History of Black Americans in the Military, page 311:
3
The act of hiding contraband, such as drugs or weapons, in one's rectum.