Very; incredibly; profoundly; to an extreme degree; dreadfully.

(now rare) Pertaining to, or resembling an abyss. / (figuratively) extremely bad; terrible.

(archaic, poetic) Hell; the infernal pit; the great deep; the primal chaos. / (now chiefly literary) An abyss; a gulf, a chasm, a very deep hole.

plural of abysm

(uncommon) Abysmal; like an abyss.