[ See Seven. ] A combining form from Gr.
n. [ Gr.
n. [ L. heptas the number seven. Gr. &unr_;, &unr_;, fr.
n. [ Cf. F. heptade. See Heptad. ] The sum or number of seven. [ 1913 Webster ]
n. [ Gr. &unr_;;
n. [ Gr. &unr_; sevencornered;
a. [ Cf. F. heptagonal. ] Having seven angles or sides. [ 1913 Webster ]
Heptagonal numbers (Arith.),
‖n. pl. [ NL., fr. Gr.
n. [ Hepta- + Gr. &unr_; seat, base, fr. &unr_; to sit: cf. F. heptaèdre. ] (Geom.) A solid figure with seven sides. [ 1913 Webster ]