noun Date: 14th century an imaginary stone, substance, or chemical preparation believed to have the power of transmuting baser metals into gold and sought by alchemists
PHILOSOPHER'S STONE
Meaning of PHILOSOPHER'S STONE in English
Merriam Webster. Explanatory English dictionary Merriam Webster. Толковый словарь английского языка Мерриам-Уэбстер. 2012