Wiktionary
vitamin f
n. An early name for the essential fatty acids
Usage examples of "vitamin f".
It also contains vitamin C, vitamin D, vitamin E, vitamin F, vitamin G, vitamin I, vitamin J, vitamin K, vitamin L, vitamin M, vitamin N, vitamin O, vitamin P, vitamin Q, vitamin R, vitamin T, vitamin U, vitamin V, vitamin W, vitamin X, vitamin Y, and, believe it or not, vitamin Z!