the GNU version of the Collaborative International Dictionary of English
adj. See harebrained.
The Century Dictionary and Cyclopedia
An erroneous spelling of harebrained.
Word Usage
"I don't know what kind of hairbrained vow he had tied up in it, but with the little ceremony disappeared every trace of restraint, and we plunged head over ears into the saturnalia of delights that was an old-time county fair."