n. 1. The horn or antler of the hart, or male red deer. [ 1913 Webster ]

2. Spirits of hartshorn (see below); volatile salts. [ 1913 Webster ]

Hartshorn plantain (Bot.), an annual species of plantain (Plantago Coronopus); -- called also buck's-horn. Booth. --
Hartshorn shavings, originally taken from the horns of harts, are now obtained chiefly by planing down the bones of calves. They afford a kind of jelly. Hebert. --
Salt of hartshorn (Chem.), an impure solid carbonate of ammonia, obtained by the destructive distillation of hartshorn, or any kind of bone; volatile salts. Brande & C.--
Spirits of hartshorn (Chem.), a solution of ammonia in water; -- so called because formerly obtained from hartshorn shavings by destructive distillation. Similar ammoniacal solutions from other sources have received the same name. [ 1913 Webster ]