1. A valued possession passed down in a family through succeeding generations.

2. Law An article of personal property that passes by custom along with the estate to an heir, instead of being subject to the executor of the estate.

3. A cultivar, especially of a vegetable or fruit, that has been cultivated for at least several decades but is not grown widely for commercial purposes. An heirloom often exhibits a distinctive characteristic such as superior flavor or unusual coloration.