True that it’s a word but a comparatively obscure one.
Answers.com definition.
ga•ble
n.
1.
a. The generally triangular section of wall at the end of a pitched roof, occupying the space between the two slopes of the roof.
b. The whole end wall of a building or wing having a pitched roof.
2. A triangular, usually ornamental architectural section, as one above an arched door or window.
I’d say low $xx to a reseller and it might be difficult to find an end user.