carnitine

noun

1. (countable, uncountable)A betaine, 3-hydroxy-4-trimethylammonio-butanoate, that is found in the liver and has a function in fatty acid transport.

   “Although often called an amino acid because of its chemical makeup, L-carnitine is actually a vitaminlike nutrient, related in structure to the B vitamins. L-carnitine is the biologically active form of carnitine.”

   “2014, Peggy R. Borum, Carnitine homeostasis in humans, Benjamin Toby Wall, Craig Porter (editors), Carnitine Metabolism and Human Nutrition, page 4, Carnitine likely functions in maintaining homeostasis in many metabolic pathways and physiological conditions, with carnitine's role in energy metabolism homeostasis being the best studied.”

   “Carnitines are quaternary amines synthesized from the amino acids lysine and methionine.”