crack·ers I. \ˈkrakə(r)z\noun plural but singular or plural in construction Etymology: so called from the cracking noise produced by the seeds when the berries are eaten : black huckleberry II. adjective Etymology: from plural of cracker (influenced in meaning by cracked, crackbrain) slang Britain: crazy < I'm here to tell you that you're driving me crackers — Noel Coward > also: intensely enthusiastic : cracked < we went crackers about them — Clarence Woodbury >