- Lyallpur
- Lycaena
- Lycaena hypophlaeas
- lycaenid
- lycaenid butterfly
- Lycaenidae
- Lycaeon
- lycanthrope
- lycanthropy
- Lycaon pictus
- lycee
- lyceum
- lychee
- lychgate
- Lychins chalcedonica
- Lychins floscuculi
- lychnis
- Lychnis alba
- Lychnis coronaria
- Lychnis dioica
- Lychnis flos-cuculi
- Lycia
- Lycian
- Lycium
- Lycium barbarum
- Lycium carolinianum
- Lycium halimifolium
- lycopene
- Lycoperdaceae
- Lycoperdales
- Lycoperdon
- Lycopersicon
- Lycopersicon esculentum
- Lycopersicon esculentum cerasiforme
- Lycopersicum
- Lycophyta
- lycopod
- Lycopodiaceae
- Lycopodiales
- Lycopodiate
- Lycopodineae
- Lycopodium
- Lycopodium alopecuroides
- Lycopodium alpinum
- Lycopodium clavitum
- Lycopodium complanatum
- Lycopodium lucidulum
- Lycopodium obscurum
- Lycopodium selago
- Lycopsida
- Lycopus
- Lycopus americanus
- Lycopus europaeus
- Lycopus virginicus
- Lycosa
- Lycosa tarentula
- Lycosidae
- Lydia
- Lydia Kamekeha Paki Liliuokalani
- Lydian
- lye
- lye hominy
- lygaeid
- lygaeid bug
- Lygaeidae
- Lyginopteridales
- Lyginopteris
- Lygodium
- Lygodium microphyllum
- Lygodium palmatum
- Lygus
- lygus bug
- Lygus lineolaris
- lying
- lying in wait
- lying under oath
- lying-in
- Lyly
- Lyman Frank Brown
- Lymantria
- Lymantria dispar
- lymantriid
- Lymantriidae
- Lyme arthritis
- Lyme disease
- lyme grass
- lymph
- lymph cell
- lymph gland
- lymph node
- lymph vessel
- lymphadenitis
- lymphadenoma
- lymphadenopathy
- lymphangiectasia
- lymphangiectasis
- lymphangiogram
- lymphangiography
- lymphangioma
- lymphangitis
- lymphatic
- lymphatic system
- lymphatic tissue
- lymphatic vessel
- lymphedema
- lymphoblast
- lymphoblast-like
- lymphoblastic leukemia
- lymphocyte
- lymphocytic
- lymphocytic choriomeningitis
- lymphocytic choriomeningitis virus
- lymphocytic leukemia
- lymphocytopenia
- lymphocytosis
- lymphogranuloma
- lymphogranuloma venereum
- lymphography
- lymphoid
- lymphoid tissue
- lymphokine
- lymphoma
- lymphopathia venereum
- lymphopenia
- lymphopoiesis
- lymphuria
- lynch
- lynch law
- lynch mob
- Lynchburg
- lynching
- lynchpin
- Lyndon Baines Johnson
- Lyndon Johnson
- Lynn Fontanne
- lynx
- Lynx canadensis
- Lynx caracal
- Lynx lynx
- Lynx pardina
- Lynx rufus
- lynx-eyed
- Lyon
- Lyonia
- Lyonia ligustrina
- Lyonia lucida
- Lyonia mariana
- Lyonnais
- lyonnaise
- Lyonnaise sauce
- Lyons
- lyophilisation
- lyophilise
- lyophilised
- lyophilization
- lyophilize
- lyophilized
- lypressin
- Lyra
- lyrate
- lyrate leaf
- lyre
- lyre snake
- lyre-flower
- lyre-shaped
- lyrebird
- lyreflower
- lyric
- lyric poem
- lyrical
- lyricality
- lyrically
- lyricism
- lyricist
- lyrist
- Lyrurus
- Lyrurus mlokosiewiczi
- Lyrurus tetrix
- Lysander
- Lysenko
- lysergic acid
- lysergic acid diethylamide
- Lysichiton
- Lysichiton americanum
- Lysichitum
- Lysiloma
- Lysiloma bahamensis
- Lysiloma latisiliqua
- Lysiloma sabicu
- Lysimachia
- Lysimachia ciliatum
- Lysimachia clethroides Duby
- Lysimachia nemorum
- Lysimachia nummularia
- Lysimachia quadrifolia
- Lysimachia terrestris
- Lysimachia vulgaris
- Lysimachus
- lysin
- lysine
- lysine intolerance
- lysinemia
- Lysippus
- lysis
- lysogenic
- lysogenicity
- lysogenisation
- lysogenization
- lysogenize
- lysogeny
- Lysol
- lysosome
- lysozyme
- lyssa
- lyssavirus
- Lythraceae
- Lythrum
- Lythrum hyssopifolia
- Lythrum salicaria
- Lytton
- Lytton Strachey
