kappa-light chain

synonym: κ-light chain
https://doi.org/10.1351/goldbook.13358
Smaller of the two types of light chain found in human immunoglobulins (Ig), the other type being a lambda ($\uplambda\!$)-light chain.
Source:
PAC, 2012, 84, 1113. (IUPAC glossary of terms used in immunotoxicology (IUPAC Recommendations 2012)) on page 1198 [Terms] [Paper]