qì​kǒng

air bubble

气孔 (氣孔) qì​kǒng
air bubble noun
a bubble of air or gas trapped in a solid material, such as metal during casting or welding
stoma noun
a microscopic pore on the surface of plant leaves or stems used for gas exchange

Frequency

Movie subtitles
0.690 per million appears in 0% of films
Written text
1.13 per million

Sources

Definitions
CC-CEDICT