What is an edible species of mushroom (Agaricus campestris). Fairy ring champignon, the Marasmius oreades, which has a strong flavor but is edible called?

champignon — An edible species of mushroom (Agaricus campestris). Fairy ring champignon, the Marasmius oreades, which has a strong flavor but is edible. (Webster's 1913.)

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