1. [1930s+] (also b.a.) naked; also fig. use; also as adv.
2. [1930s+] pertaining to striptease, sex.
3. [1960s] in fig. use, naïve [the image is of a bare-bottomed infant].
4. [1960s] (US) minimal.
5. [1970s] (US Und.) of a burglar, not wearing any gloves (to prevent identification).