noun (n)

• common name for an inedible or poisonous agaric (contrasting with the edible mushroom)(noun.plant)

  Antonym:
  mushroom
  

  source: wordnet30
• A name given to many umbrella-shaped fungi, mostly of the genus Agaricus. The species are almost numberless. They grow on decaying organic matter.(noun)

  source: webster1913