bilateral asymmetry; left-right asymmetry
Technical term used in biology, anatomy, engineering, and design to describe a lack of symmetry between the left and right sides.
This organism has a bilaterally asymmetrical body.
左右非対称なデザインが特徴的だ。
The design is characterized by left-right asymmetry.
Because of the illness, his face became asymmetric between left and right.
She was wearing earrings with an asymmetric design.
The architect deliberately made this building asymmetric.
非対称 is the general term for any kind of asymmetry, while 左右非対称 specifically narrows it to a left-right mismatch.
左右対称 describes bilateral symmetry, the exact opposite of 左右非対称's lack of symmetry between left and right sides.
Compound of 左右 (left and right) + 非対称 (asymmetry). The exact historical derivation is uncertain, but the term is a straightforward modern technical coinage.