Rising main

from The Collaborative International Dictionary of English v.0.48

Rising \Ris"ing\, n.
   1. The act of one who, or that which, rises (in any sense).
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   2. That which rises; a tumor; a boil. --Lev. xiii. 10.
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   {Rising main} (Waterworks), the pipe through which water from
      an engine is delivered to an elevated reservoir.
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