Source : Webster's Revised Unabridged Dictionary (1913)

Ogive \O"give\, n. [F. ogive, OF. augive a pointed arch, LL.
   augiva a double arch of two at right angles.] (Arch.)
   The arch or rib which crosses a Gothic vault diagonally.

Source : WordNet®

ogive
     n : front consisting of the conical head of a missile or rocket
         that protects the payload from heat during its passage
         through the atmosphere [syn: {nose cone}]