A hinge where each leaf is equal and meets together giving effectively two (2) leaves thickness in closed position. Found on https://www.encyclo.co.uk/local/21289
A hinge that allows the full closing of a door or window. Butt hinges stand proud of the door or window surface. Found on https://www.eurocell.co.uk/glossary
a hinge for a door or the like, secured to the butting surfaces rather than to the adjacent sides of the door and its frame. Cf. flap (def. 20a). See illus. under Found on https://www.infoplease.com/dictionary/butt-hinge