From the OED
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vermilion, n. and a. Forms: . 3 vermelyon, 6 -eleon, -eleoun; 45 vermilyon, 5 -ylyoun, 56 -ylyon(e, 6 -ylion; 45 vermilioun, 5 vermilion (67 -milian, 7 virmilion). . 4 vermeillone, 5 -elone, 57 -elon, 6 Sc. -eloun; 45 vermylone, 4 fer-, 5 vermyloun, 56 vermylon; 45 vermulon, 45 vermilon(e, -iloun; also 6 vermelonde, Sc. wermeling, -myling. . 69 vermillion, 7 virmillion.
[a. AF. and OF. vermeillon, vermillon, vermilo(u)n, etc. (mod.F. vermillon, = Prov. vermeillon, vermillon, vermelho, Cat. bermello, Sp. bermellon, bermillon, vermellon, Pg. vermelhaõ, It. vermiglione), f. vermeil vermeil a. Hence also Du. vermiljoen, Da. and Sw. vermilion.]
A. n.
1. Cinnabar or red crystalline mercuric sulphide, esp. in later use that obtained artificially, much valued on account of its brilliant scarlet colour, and largely used as a pigment or in the manufacture of red sealing-wax; also, any red earth resembling this and similarly used as a pigment.
In early use rendering L. minium and occas. confused with red lead' (as in quot. 1546 in ): see minium.
b. Used as a cosmetic or for painting the body.
In later use chiefly with reference to the war-paint' of the American Indians.
2. The colour of this pigment; a bright red or scarlet.
b. A blush. Obs.1
3. a. (Rendering L. vermiculum.) Wool or yarn of a red or scarlet colour. Obs.
b. A fabric dyed with vermilion. Obs.1
4. A red or reddish coloured variety of pear.
5. (Also vermilion-stone.) A particular gem or precious stone. Cf. vermeil n. 3. Obs.
6. a. Comb., as vermilion-dyed, -like adjs.;
b. attrib. with colour, etc. (passing into next); hence in combs., as vermilion-coloured.