vitamin k(n = noun.substance) antihemorrhagic factor, naphthoquinone - a fat-soluble vitamin that helps in the clotting of blood;
is a kind of fat-soluble vitamin
has particulars: phylloquinone, phytonadione, vitamin k1, menadione, vitamin k3

   either of two fat-soluble vitamins (vitamin K1 or vitamin K2) that help clot blood by participating in the fromation of prothrombin. [WordNet 1.5]

b vitamin, b-complex vitamin, fat-soluble vitamin, k, k particle, k ration, letter k, special k, vitamin, vitamin a, vitamin a1, vitamin a2, vitamin b, vitamin b complex, vitamin b1, vitamin b12, vitamin b2, vitamin b3, vitamin b5, vitamin b6, vitamin bc, vitamin c, vitamin d, vitamin deficiency, vitamin e, vitamin g, vitamin h, vitamin k1, vitamin k2, vitamin k3, vitamin m, vitamin p, vitamin pill, water-soluble vitamin