The Collaborative International Dictionary of English v.0.48:
Miasmal \Mi*as"mal\, a. Containing miasma; miasmatic. [1913 Webster] MiasmaticWordNet (r) 3.0 (2006):
miasmal adj 1: filled with vapor; "miasmic jungles"; "a vaporous bog" [syn: miasmal, miasmic, vaporous, vapourous]