concave

A Dictionary of Aviation · 1911 · p. 7
ken‘keev, (a umptivly) ‘ken,kev adj..having the outline or surface curvd like the anterior of a circle or sfere: the reverse of cenvex; hollow; presenting a hollow surface to view; incurvated. coneave ‘ken,kev m. the arch or vault of heven; the hevens; as, the blue *cencave. conecaved ’ken,kevd adj. made or fashiond in a cencave form; cencave.
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