any of a large group of nitrogenous organic compounds that are essential constituents of living cells; consist of polymers of amino acids; essential in the diet of animals for growth and for repair of tissues; can be obtained from meat and eggs and milk and legumes; "a diet high in protein"
a rocket-propelled guided missile that can escape the earth's atmosphere; makes observations of the solar system that cannot be made by terrestrial observation
a surface excavation for extracting stone or slate; "a British term for `quarry' is `stone pit'"
a trap in the form of a concealed hole
a sizeable hole (usually in the ground); "they dug a pit to bury the body"
a concavity in a surface (especially an anatomical depression)
remove the pits from; "pit plums and cherries"
set into opposition or rivalry; "let them match their best athletes against ours"; "pit a chess player against the Russian champion"; "He plays his two children off against each other"