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

humin \hu"min\, n. l. humus the earth, ground. chem.
   a bitter, brownish yellow, amorphous substance, extracted
   from vegetable mold, and also produced by the action of acids
   on certain sugars and carbohydrates; -- called also humic
   acid, ulmin, gein, ulmic or geic acid, etc.
   1913 webster
see also:
humic acid ulmin gein ulmic geic acid 

[2] : WordNet (r) 2.0

humin
     n : a black humic substance that is not soluble in water

Humin >> H Words
Humin, definition of term: Humin
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