n. pl. di·as·ta·ses (-sēz′)
1. Separation of normally joined anatomical parts, as of certain abdominal muscles during pregnancy.
2. The last stage of diastole in the heart, occurring just before contraction and during which little additional blood enters the ventricle.
[Greek, separation, from diistanai, to separate : dia-, apart; see DIA- + histanai, to cause to stand; see stā- in the Appendix of Indo-European roots.]
di′a·static (dī′ə-stătĭk) adj.
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