hartshorn
/ˈhɑrtsˌhɔrn/
noun
- A substance made from the antlers of a deer, historically used as a source of ammonia or in baking as a leavening agent.
- In the 18th century, hartshorn was commonly used in smelling salts.
- The old recipe called for hartshorn to make the cookies light and crispy.
- The baker substituted baking powder for hartshorn in the modern version of the cake.