Definitions for nyssaceae
Nyssaceae, family Nyssaceae, sour-gum family, tupelo family(noun)
a family of dicotyledonous trees of order Myrtales that includes the sour gum trees
U.S. National Library of Medicine
A plant family of the order Cornales, subclass Rosidae, class Magnoliopsida. Some botanical classifications do not recognize this family and place the members in CORNACEAE.