[1] : The Collaborative International Dictionary of English v.0.48

nutrient \nu"trient\, a. l. nutriens, p. pr. of nutrire. see
   nourish.
   nutritious; nourishing; promoting growth.
   1913 webster
see also:
nourish 

[2] : The Collaborative International Dictionary of English v.0.48

nutrient \nu"trient\, n. n.
   1. any substance which has nutritious qualities, i. e., which
      nourishes or promotes growth; a nutriment.
      1913 webster

   2. specifically: microbiology a substance added to the
      growth medium of a microorganism to promote growth.
      pjc

[3] : WordNet (r) 2.0

nutrient
     adj : of or providing nourishment; "good nourishing stew" syn: alimentary,
            alimental, nourishing, nutritious, nutritive
     n : any substance that can be metabolized by an organism to give
         energy and build tissue syn: food
see also:
alimentary alimental nourishing nutritious nutritive food 

Nutrient >> N Words
Nutrient, definition of term: Nutrient
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Nutrient Agar >> N Words
Nutrient Agar, definition of term: Nutrient Agar
nutrient+agar_pag1.html