a yellowish, oily, viscous liquid, C 31 H 46 O 2 , occurring in leafy vegetables, rice, bran, hog liver, etc., or obtained esp. from alfalfa or putrefied sardine meat, or synthesized, that promotes blood clotting by increasing the prothrombin content of the blood. Also called phylloquinone, phytonadione .
[ 1930-35 ]