Webster's Revised Unabridged Dictionary · 1913

Hogback

Hogback , noun

1.
(Architecture) An upward curve or very obtuse angle in the upper surface of any member, as of a timber laid horizontally; -- the opposite of camber.
2.
(Nautical) See Hogframe.
3.
(Geology) A ridge formed by tilted strata; hence, any ridge with a sharp summit, and steeply sloping sides.