trimethylamine
noun
tri·meth·yl·amine
| \ ˌtrī-ˌmeth-ᵊl-ˈam-ˌēn, -ə-ˈmēn
\
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Medical Definition of trimethylamine
: an irritating gaseous or volatile liquid tertiary amine (CH3)3N that has a fishy odor, is only slightly more basic than ammonia, is flammable and forms explosive mixtures with air, is formed as a degradation product of many nitrogenous animal and plant substances, and is used chiefly in making quaternary ammonium compounds (as choline)