breathable
adj.allowing air to pass through easily. You use this to describe fabrics that let your skin stay cool or masks that do not make you feel stuffy.
adj.permitting the passage of air or gas through a material. Often used to describe textiles, masks, or environmental conditions.
“This cotton shirt is very breathable and comfortable in the summer.”
“The new surgical mask is designed to be more breathable while still providing a high level of filtration.”
“Engineers are developing a new type of breathable concrete that allows moisture to escape, preventing the structural decay caused by trapped humidity in coastal environments.”
“T hat certain physical conditions are necessary for the development of life has been recognised for a long time: distance from the sun, the presence of water, a breathable atmosphere.”
From breathe + -able.
Etymology adapted from Wiktionary, available under CC BY-SA 4.0.