amanitin

noun

1. (countable, uncountable)A deadly amatoxin found in Amanita phalloides (the death cap), the four destroying angels (Amanita bisporigera, Amanita ocreata, Amanita verna, and Amanita virosa), and some other amanitas.

   “Death caps contain a poison called amanitin which, according to the UK's Woodland Trust, is responsible for 90 per cent of all fatalities caused by ingesting fungus.”