| KC | KeratoConus |
| KCCM | Korean Culture Center of Microorganism |
| KCE | Kinetic Capillary Electrophoresis |
| KCS | Kerato Conjunctivitis Sicca |
| KGF | Keratinocyte Growth Factor |
| KID | Kinase Inducible Domain |
| KLG | Keto L Gulonic (acid, ascorbic acid) |
| KLH | Keyhole Limpet Hemocyanin |
| KM | Knowledge MAN. |
| KOL | Key Opinion Leaders |
| KOR | kappa opioid receptor |
| KR | KoReia (South) |
| KRAS | Kirsten Rat Sarcoma Virus |
| KSHV | Kaposi's Sarcoma Herpes Virus |
| KSP | Kinesin Spindle Protein |
| KTA | Kilo Tons per Annum |
| KVCT | Kilo Voltage Computed Tomography |