owned by or resembling a bat
- informal or slang terms for psychologically irregular
- owned by, or resembling, a bat.
1580s, "pertaining to bats," from bat (n.2) + -y (2). Slang good sense "nuts, crazy" is attested from 1903, from expression (to possess) bats in (one's) belfry, in addition indicating "not be in your head" (1899).
(a.) Belonging to, or resembling, a bat.