ˌmenəˈdīˌōn noun
( -s )
Etymology: me thyl + na phthoquinone + -dione
: a yellow crystalline compound C 11 H 8 O 2 that is usually made by oxidation of beta-methylnaphthalene, that has the biological activity of natural vitamin K to which it is chemically related, and that is often administered in the form of a water-soluble white crystalline addition compound with sodium bisulfite; 2-methyl-1,4-naphthoquinone — called also vitamin K 3