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1640s, from Latin vitreus "of glass, glassy," from vitreum "glass," which perhaps was so called for its color (cf. vitrium "woad"). Vitreous humor attested from 1660s.
vitreous vit·re·ous (vĭt'rē-əs)
Of, relating to, resembling, or having the nature of glass; glassy.
Of or relating to the vitreous body.