a nonmetallic bivalent element that is normally a colorless odorless tasteless nonflammable diatomic gas; constitutes 21 percent of the atmosphere by volume; the most abundant element in the earth's crust
a common nonmetallic element that is normally a colorless odorless tasteless inert diatomic gas; constitutes 78 percent of the atmosphere by volume; a constituent of all living tissues
a heavy odorless colorless gas formed during respiration and by the decomposition of organic substances; absorbed from the air by plants in photosynthesis
soft coarse splintery wood of a hemlock tree especially the western hemlock
large branching biennial herb native to Eurasia and Africa and adventive in North America having large fernlike leaves and white flowers; usually found in damp habitats; all parts extremely poisonous
poisonous drug derived from an Eurasian plant of the genus Conium; "Socrates refused to flee and died by drinking hemlock"
a very poisonous metallic element that has three allotropic forms; arsenic and arsenic compounds are used as herbicides and insecticides and various alloys; found in arsenopyrite and orpiment and realgar
a white powdered poisonous trioxide of arsenic; used in manufacturing glass and as a pesticide (rat poison) and weed killer
a volatile flammable mixture of hydrocarbons (hexane and heptane and octane etc.) derived from petroleum; used mainly as a fuel in internal-combustion engines
an alkaloidal extract or tincture of the poisonous belladonna plant that is used medicinally
perennial Eurasian herb with reddish bell-shaped flowers and shining black berries; extensively grown in United States; roots and leaves yield atropine
a chemical substance derivable from a mold or bacterium that kills microorganisms and cures infections; "when antibiotics were first discovered they were called wonder drugs"