- Koro
- Korotkoff sound
- Korotkoff sounds
- Korsakoff psychosis
- Korsakoff syndrome
- Korsakoff's syndrome
- Kounis syndrome
- Kovac's reagent
- Kozak consensus sequence
- Krabbe disease
- Krafft temperature
- Krause's end-bulbs
- Krause's glands
- Krebs cycle
- Kriging
- Krill oil
- Kringle domains
- Krukenberg tumor
- Krukenberg's spindle
- Kruppel-like factors
- Kruskal-Wallis test
- Krypton-85
- Kt/v
- Kuder-Richardson formulas
- Kudzu
- Kufor-Rakeb syndrome
- Kunitz domain
- Kunjin virus
- Kupffer cells
- Kussmaul breathing
- Kussmaul's sign
- Kv
- KvLQT1
- Kwashiorkor
- Kyasanur Forest Disease Virus
- Kyasanur Forest disease
- Kymograph
- Kynurenic acid
- Kynureninase
- Kynurenine
- Kynurenine 3-monooxygenase
- Kyphoplasty
- Kyphoscoliosis
- Kyphosis
- Kytococcus sedentarius
- L amino acid oxidase
- L glucose
- L ring
- L thyroxine
- L-Dopa
- L-Dopaquinone
- L-alanine
- L-dopa
- L-form bacteria
- L-gulonolactone oxidase
- L-moment
- L-type calcium channels
- L-tyrosine
- L-xylulose reductase
- L1
- L1CAM
- LABA
- LAD1
- LAMP1
- LAMP2
- LAMP3
- LANA
- LAPC4
- LATS1
- LATS2
- LC50
- LCAT
- LCIS
- LCK
- LD50
- LDL
- LDL apheresis
- LDL receptor
- LE cell
- LEF1
- LETM1
- LFA-1
- LFA-3
- LGBT
- LGP2
- LGR5
- LH
- LHCGR
- LHON
- LHX3
- LIF
- LIG4
- LIG4 syndrome
- LILRB1
- LILRB4
- LIM domain
- LIMS
- LINE
- LMNA
- LNCaP
- LOAEL
- LOINC
- LONP1
- LOX1
- LPB
- LPC
- LPCA
- LRBA deficiency
- LRP1
- LRRC8A
- LRRK2
- LSD
- LSm
- LTC4 synthase
- LTP
- LTP induction
- LTR retrotransposons
- LUCA
- LY294002
- LYL1
- LYN
- LYVE1
- LZTFL1
- Labdane
- Label-free quantification
- Labetalol
- Labia majora
- Labia minora
- Labial
- Labial fusion
- Labial glands
- Labiaplasty
- Labile hypertension
- Lability
- Labioscrotal folds
- Labioscrotal swelling
- Labisia pumila
- Labium
- Labor induction
- Laboratory automation
- Laboratory experiment
- Laboratory glassware
- Laboratory safety
- Laboratory-acquired infection
- Labored breathing
- Labral
- Labral reconstruction
- Labyrinthectomy
- Labyrinthine artery
- Labyrinthine fistula