Source : Webster's Revised Unabridged Dictionary (1913)

Quinquevalve \Quin"que*valve\, Quinquevalvular
\Quin`que*val"vu*lar\, a. [Quinque- + valve, valvular: cf. F.
   quinqu['e]valve.] (Bot.)
   Having five valves, as a pericarp.