antagonist: a muscle that relaxes while another contracts
antagonistic muscle: (physiology) a muscle that opposes the action of another
gastrocybe lateritia: a species of Gastrocybe fungus that has a conic cap and a thin stalk; at first the stalk is upright but as it matures the stalk bends over and then downward; the cap then gelatinizes and a slimy mass containing the spores falls to the ground as the stalk collapses