FSL may refer to:
Language Filipino Sign Language Finnish Sign Language French Sign Language
Other uses Fast Simplex Link, a soft microprocessor bus Few-shot learning, a machine learning method Fiji Senior League, a football league in Fiji Fleet Support Limited, a British logistics company Florida State League, an American minor baseball league Fluid Science Laboratory, on the International Space Station FMRIB Software Library FM FSL, a rifle Folger Shakespeare Library in Washington, D.C., United States Forecast Systems Laboratory of the United States National Oceanic and Atmospheric Administration Fox Sports Live, an American television program Fraternitas Scintilla Legis, a Philippine fraternity Freescale Semiconductor, an American semiconductor manufacturer Free-space loss Friends' School, Lisburn, in Northern Ireland Function-spacer-lipid construct