- Livida, asphyxia
- Living
- Lloyd's syndrome 258.1
- Loa loa 125.2
- Loasis 125.2
- Lobe, lobar - see condition
- Lobo's disease or blastomycosis 116.2
- Lobomycosis 116.2
- Lobotomy syndrome 310.0
- Lobstein's disease (brittle bones and blue sclera) 756.51
- Lobster-claw hand 755.58
- Lobulation (congenital) - see also Anomaly, specified type NEC, by site
- Lobule, lobular - see condition
- Local, localized - see condition
- Locked bowel or intestine (see also Obstruction, intestine) 560.9
- Locked twins 660.5
- Locked-in state 344.81
- Locking
- Lockjaw (see also Tetanus) 037
- Locomotor ataxia (progressive) 094.0
- Löffler's
- Löfgren's syndrome (sarcoidosis) 135