n 1  :  a device that raises, transfers, or compresses fluids or that attenuates gases esp. by suction or pressure or both  2  :  HEART  3  :  an act or the process of pumping  4  :  an energy source (as light) for pumping atoms or molecules  5  :  a mechanism (as the sodium pump) for pumping atoms, ions, or molecules
vi :  to work a pump  :  raise or move a fluid with a pump vt  1  :  to raise (as water) with a pump  2  :  to draw fluid from with a pump  3  :  to transport (as ions) against a concentration gradient by the expenditure of energy  4 a  :  to excite (as atoms or molecules) esp. so as to cause emission of coherent monochromatic electromagnetic radiation (as in a laser)  b  :  to energize (as a laser) by pumping .
 
 
 
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