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Definition of Boiling water reactor
1. Noun. A nuclear reactor that uses water as a coolant and moderator; the water boils in the reactor core and the steam produced can drive a steam turbine. 
Medical Definition of Boiling water reactor
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1. Noun. A nuclear reactor that uses water as a coolant and moderator; the water boils in the reactor core and the steam produced can drive a steam turbine. 
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