| FA | Fumaric Acid. anhydride (polymer) |
| FA Neuro. | Friedreichs Ataxia |
| FAA | Federal Aviation Administration |
| FAAH | Fatty Acid Amide Hydrolase |
| FAB | Fast Atom Bombardment (mass spectroscopy) |
| FAB | Fatty Acid Biosynthesis |
| FAB | Fragment Anti Body |
| FAC | Familial Amyloidotic Cardiomyopathy |
| FACS | Fluorescence Activated Cell Sorting |
| FAD | Flavin Adenine Dinucleotide |
| FAI | Femoro Acetabular Impingement |
| FAK | Focal Adhesion Kinase |
| FAP | Familial Amyloidotic Polyneuropathy |
| FAP | Fatty Acid Photodecarboxylase |
| FAP | Fibroblast Activation Protein |
| FAP Onco. | Familial Adenomatous Polyposis |
| FAPESP | Fundação Amparo Pesquisa Estado São Paulo (Brazil) |
| FAS | Fatty Acid Synthase |
| FAST | For Angioedema Subcutaneous Treatment |
| FBD | Fibrin Binding Domain |
| FBLD | Fragment Based Lead Discovery |
| FC Gastro. | functional constipation |
| FC Neuro | Functional Connectome |
| FCC | Fluidized Cracking Catalyst |
| FCC | Fluid Catalytic Cracking |
| FcRn | Fc Receptor neonatal |
| FCS | Fetal Calf Serum |
| FCS | Fluorescence Cross-correlation Spectroscopy |
| FCS Endo | Familial Chylomicronemia Syndrome |
| FDA | Food & Drug Administration (USA Government) |
| FDA | Fluoro Deoxy Adenosine |
| FDCA | Furan Di Carboxylic Acid |
| FDI | Foreign Direct Investment |
| FDM | Fused Deposition Modeling |
| FDP | Fructose Di Phosphate |
| FDP | Finished Dosage Products |
| FED | Field Emission Displays |
| FEL | Free Electron Laser |
| FEP | Fluoro Ethylene Propylene resin |
| FERC | Federal Energy Regulatory Commission (USA government) |
| FET | Field Effect Transistor |
| FFA | Free Fatty Acid |
| FFDM | Full Field Digital Mammography |
| FFPE | Formalin Fixed Paraffin Embedded |
| FFR | Fractional Flow Reserve |
| FFT | Fast Fourier Transform |
| FG | Fibrino Gen |
| FGF | Fibroblast Growth Factor |
| FGFR | Fibroblast Growth Factor Receptor |
| FGM | Functional Graded Material |
| FH | Familial Hypercholesterolemia |
| FHA | Filamentous Hem Agglutinin |
| FHE | Fully Homomorphic Encryption |
| FHF | FGF Homologous Factor |
| FHR | fetal heart rate |
| FHV | Flock House Virus |
| FI | Fecal Incontinence |
| FID | Flame Ionization Detector |
| FIDO | Fast ID Online |
| FIE | Feuerstein Instrumental Enrichment |
| FISH | Fluorescence In Situ Hybridization |
| FITC | Fluorescein Iso Thio Cyanate |
| FIV | Feline Immunodeficiency Virus |
| FKBP | FK506 (Immunosuppressive drug) Binding Protein |
| FL | Follicular Lymphoma |
| FLCOS | Ferroelectric Liquid Crystal On Silicon |
| FLE | Fluorescent Light Energy |
| FLEXGene | Full Length EXpression-ready Gene (Proteomics) |
| FLINC | Fluorescence fLuctuation INcrease by Contact |
| FLT | Fluorescence Lifetime Technology |
| FLT Onco. | FMS-Like Tyrosine kinase |
| FMD | Foot & Mouth Disease |
| FMDV | Foot & Mouth Disease Virus |
| FMN | Flavin Mono Nucleotide |
| FMOC | Fluorenyl Methyl Oxy Carbonyl |
| FMR | Functional Mitral Regurgitation |
| FMS | Fluorous Multiphase Systems |
| FMS | Fluorous Mixture Synthesis |
| FMS Rheuma | Fibro Myalgia Syndrome |
| FNIRS | Functional Near IR Spectroscopy |
| FOB | Follow-On Biologics |
| FOC | Free Of Charge |
| FOP | fibrodysplasia ossificans progressiva |
| FORN | Focused Resonance Nano-Permeabilization |
| FOUND | Foundation |
| FOX | Fluorinated Oxetane (monomer) |
| FPA | Flavor Profile Analysis |
| FPC | Flexible Printed Circuit |
| FPD | Flat Panel Display |
| FPGA | Field Programmable Gate Arrays |
| FPIA | Fluorescence Polarization Immuno Assay |
| FPPS | Farnesyl Pyro Phosphate Synthase |
| FQPA | Food Quality Protection Act (USA Legislation) |
| FR | Fire Retardant |
| FR | Framework Region |
| FR | FRance |
| FRα | Folate Receptor Alpha |
| FRAP | FKBP Rapamycin Associated Protein |
| FRCMC | Fiber Reinforced Ceramic Matrix Composite |
| FRDA | FRieDreich s Ataxia |
| FRET | Fluorescence Resonance Energy Transfer |
| FRET | Forster Resonance Energy Transfer |
| FRP | Fiber Reinforced Plastic |
| FSA | Fluo Silicic Acid (H2SiF6) |
| FSCT | Federation of Societies for Coatings Technology |
| FSD | Female Sexual DysFunction |
| FSG | Fluorinated Silicate Glass (electronics) |
| FSH | Follicle Stimulating Hormone |
| FSHD | FacioScapulohumeral Muscular Dystrophy |
| FSS | Functional Somatic Syndromes |
| FST | Full-field Sensitivity Threshold |
| FT | Fracture Toughness |
| FT | Fourier Transform (IR spectrometry) |
| FT | Fischer Tropsch |
| FTC | Federal Trade Commission (USA Government) |
| FTD | Fronto Temporal Dementia |
| FTE | Full Time Equivalent (Pharma.) |
| FTI | Farnesyl Transferase Inhibitor |
| FTIR | Fourier Transform Infra Red |
| FTMS | Fourier Transform Mass Spectrometry |
| FU | Fluoro Uracil |
| FVP | Flash Vacuum Pyrolysis |
| FXR | Farnesoid X Receptor |