FL or variations may refer to:
Businesses and organizations
- FL, IATA code of Fly Lili, a Romanian airline
- FL, then-IATA code of AirTran Airways, a former American airline
- FL Group, an Icelandic investment company
- Foot Locker (ticker symbol), retailer
Numismatics
- Florin (disambiguation), various coins
- Guilder, various coins also sometimes called "florin"
Places
- Florida, US postal abbreviation
Science and technology
Biology and medicine
- FLT3LG (Fms-related tyrosine kinase 3 ligand), a protein
- Fluffy transcription factor, gene of Neurospora crassa
- Fluorouracil (5-FU), and leucovorin (folinic acid), a chemotherapy regimen
- Follicular lymphoma in medicine
- Frontal lobe, the largest brain lobe
Mathematics and computing
- FL (complexity), a class of functions
- FL (programming language)
- FL Studio, music production software
Other uses in science and technology
- Femtolitre, a unit of volume
- Flerovium, symbol Fl, a chemical element
- Flight level, of an aircraft
- "Fluid", as in fluid ounce (fl oz)
- Foot-lambert, a unit of luminance
- Friedmann–Lemaître metric in cosmology
Sport
- Federal League, a 1914–1915 US baseball league
- English Football League
Genealogy
- Floruit (abbreviated fl.), a date when someone was active
Other uses
- fl, a typographical ligature
- Flavius, a family or personal name in ancient Rome
- Flawless, a grade of diamond clarity
- Fork length, a standard fish measurement
- Free List (Liechtenstein), a political party
- Volvo FL, a truck
- Front Left speaker in 5.1 surround sound