- Lichen nitidus
- Lichen planus
- Lichen sclerosus
- Lichen sclerosus et atrophicus
- Lichen spinulosus
- Lichen striatus
- Lichenin
- Lichenoid
- Lichens
- Licking
- Licofelone
- Licorice
- Lid lag
- Liddle syndrome
- Liddle's syndrome
- Lidocaine
- Lidocaine prilocaine
- Lie detection
- Liebowitz social anxiety scale
- Life Events and Difficulties Schedule
- Life expectancy
- Life extension
- Life history
- Life satisfaction
- Life story work
- Life support
- Life tables
- Life-events and difficulties schedule
- Life-years lost
- Lifelong learning
- Lifespan
- Lifestyle
- Lifestyle diseases
- Lifestyle drugs
- Lifestyle medicine
- Lifestyle modification
- Lifitegrast
- Lig4 syndrome
- Ligament
- Ligamentotaxis
- Ligamentous laxity
- Ligamentum arteriosum
- Ligamentum flavum
- Ligamentum venosum
- Ligand
- Ligand binding
- Ligand binding assay
- Ligand efficiency
- Ligand-gated ion channel
- Ligand-gated ion channels
- Ligase Chain Reaction
- Light Scattering Spectroscopy
- Light absorption
- Light amplification by stimulated emission of radiation
- Light beam
- Light chain
- Light chain deposition disease
- Light element
- Light emitting diodes
- Light field microscopy
- Light rays
- Light scattering
- Light sheet fluorescence microscopy
- Light therapy
- Light transmission
- Light-chain deposition disease
- Light-dark box test
- Light-harvesting complexes
- Light-sheet microscopy
- Lightheadedness
- Lightness
- Lignans
- Lignin
- Lignin peroxidase
- Lignite
- Lignoceric acid
- Ligstroside
- Ligusticum chuanxiong
- Ligustilide
- Likelihood ratio
- Likert scale
- Likert type scale
- Lilrb1
- Lilrb4
- Lily of the valley
- Lim kinase
- Lima beans
- Limb
- Limb Body Wall Complex
- Limb bud
- Limb perfusion
- Limb-girdle muscular dystrophy
- Limbal relaxing incisions
- Limbal stem cell
- Limbal stem cell deficiency
- Limbic cortex
- Limbic encephalitis
- Limbic lobe
- Limbic system
- Limen
- Limen insulae
- Limewater
- Limit of detection
- Limiting reagent
- Limonene
- Limonin
- Limonoid
- Limp
- Limulus amebocyte lysate
- Linaclotide
- Linagliptin
- Linalool
- Linalyl acetate
- Linamarase
- Lincosamides
- Lindane
- Lindley's paradox
- Line of Gennari
- Line source
- Linea alba
- Linea aspera
- Linea semilunaris
- Lineage selection
- Linear IgA bullous dermatosis
- Linear accelerator
- Linear energy transfer
- Linear epitope
- Linear gingival erythema
- Linear no threshold model
- Linear scleroderma
- Lines of Zahn
- Lineweaver-Burk plot
- Linezolid
- Lingual artery
- Lingual frenectomy
- Lingual frenulum
- Lingual gyrus
- Lingual lipase
- Lingual nerve
- Lingual papillae
- Lingual thyroid
- Lingual tonsils
- Lingual vein
- Lingual veins
- Linguistic performance
- Linguistic validation
- Liniments
- Linitis plastica
- Linkage analysis
- Linkage disequilibrium