Chinese character 綳

綳 means to bind or pull something tight. It is a recorded variant of 繃. Depending on the object, the word can describe tightening cloth or rope, securing fibers, holding fabric in place with loose stitches before sewing, or keeping a face stiff.

The Han-period Chinese dictionary 《說文解字》 defines 繃 as binding and illustrates it with Yu's coffin wrapped in kudzu vines. Later Taiwanese dictionaries also record a cloth sling for carrying a child and a frame for embroidery. These uses keep the word close to things held taut.

What does 綳不住了 mean?

It means someone cannot hold back a reaction. After a joke, it usually means “I cracked”; it can also cover tears, anger, or another response that breaks through an effort to stay composed. Literally, 不住 adds the sense that the tension cannot be held.

Traditional Chinese commonly writes 繃, with 綳 listed as a variant; simplified Chinese uses 绷. The written form changes with the script convention, not the reaction's meaning.