miasma

A noxious atmosphere or influence.

A poisonous atmosphere formerly thought to rise from swamps and putrid matter and cause disease.

A thick vaporous atmosphere or emanation.

The emanations or effluvia arising from the ground and floating in the atmosphere, considered to be infectious or otherwise injurious to health; noxious emanations; malaria. Also called aërial poison.

Infectious particles or germs floating in the air; air made noxious by the presence of such particles or germs; noxious effluvia; malaria.

A noxious atmosphere or influence.

A noxious atmosphere or emanation once thought to originate from swamps and waste to cause disease.

unhealthy vapors rising from the ground or other sources

an unwholesome atmosphere