Not open to a free current of air wanting fresh air or communication with the open air
- lacking fresh air
- maybe not available to a totally free current of atmosphere; wanting fresh air, or interaction because of the open-air.
(a.) Maybe not available to a free of charge existing of atmosphere; wanting oxygen, or communication with the open air.
The stems are frequently characterized by aeration channels, which connect the aerial parts with the parts which are buried in practically airless mud or silt.