The Collaborative International Dictionary of English v.0.48:
bog \bog\ (b[o^]g), n. [Ir. & Gael. bog soft, tender, moist: cf.
Ir. bogach bog, moor, marsh, Gael. bogan quagmire.]
1. A quagmire filled with decayed moss and other vegetable
matter; wet spongy ground where a heavy body is apt to
sink; a marsh; a morass.
Appalled with thoughts of bog, or caverned pit,
Of treacherous earth, subsiding where they tread.
2. A little elevated spot or clump of earth, roots, and
grass, in a marsh or swamp. [Local, U. S.]
Bog bean. See Buck bean.
Bog bumper (bump, to make a loud noise), Bog blitter,
Bog bluiter, Bog jumper, the bittern. [Prov.]
Bog butter, a hydrocarbon of butterlike consistence found
in the peat bogs of Ireland.
Bog earth (Min.), a soil composed for the most part of
silex and partially decomposed vegetable fiber. --P. Cyc.
Bog moss. (Bot.) Same as Sphagnum.
Bog myrtle (Bot.), the sweet gale.
Bog ore. (Min.)
(a) An ore of iron found in boggy or swampy land; a
variety of brown iron ore, or limonite.
(b) Bog manganese, the hydrated peroxide of manganese.
Bog rush (Bot.), any rush growing in bogs; saw grass.
Bog spavin. See under Spavin.