[hy.pos.ta.sis] n, pl -ta.ses [LL, substance, sediment, fr. Gk, support, foundation, substance, sediment, fr. hyphistasthai to stand under, support, fr. hypo- + histasthai to be standing--more at stand] (1590) 1 a: something that settles at the bottom of a fluid b: the settling of blood in the dependent parts of an organ or body
2: person 3 3 a: the substance or essential nature of an individual b: something that is hypostatized
4. [NL, fr. LL]: failure of a gene to produce its usual effect when coupled with another gene that is epistatic toward it -- hy.po.stat.ic adj -- hy.po.stat.i.cal.ly adv