Definition from Wiktionary, the free dictionary
Han character 
- level ground
- Japanese, Taiwanese, and Korean measure of area
- KangXi: page 226, character 22
- Dai Kanwa Jiten: character 4976
- Dae Jaweon: page 461, character 34
- Hanyu Da Zidian: volume 1, page 430, character 9
- Unihan data for U+576A
坪 (Yale ping4)
Cognate with 壺 (tsubo, "a basin"). The current meaning related to area arose from the way a surrounded area with the base or floor lower than the circumference looks like a basin.
- A unit of areal measure, in modern usage equivalent to 3.306 square metres, traditionally equivalent to the area covered by two standard-sized tatami mats.
- pyeong, a traditional unit of measurement
- a traditional measurement of area equal to about 3.306 square meters, roughly 35.57 square feet