a heavy or foul-smelling vapour, e.g. one from a swamp formerly believed to cause disease
a pervasive influence or atmosphere that tends to weaken or corrupt
the miasma of poverty
miasmal adj
miasmatic /mee·əzʹmatik/ adj
miasmic /-mik/ adj
[via Latin from Greek miasma defilement, from miainein to pollute]