| Flabiol | Flabiol |
| FLAC | Free Lossless Audio Codec |
| flaccidez | flabbiness |
| Flacio Illirico | Matthias Flacius |
| flaco | slim |
| FLACSO | Latin American Social Sciences Institute |
| Flacurtiaceae | Flacourtiaceae |
| flagelación | flagellation |
| flagelante | flagellant |
| flagelar | flagellate |
| Flagelarse | Cat |
| Flagellariaceae | Flagellariaceae |
| Flagelo | Flagellum |
| flagrante | sheer |
| Flags of Our Fathers | Flags of Our Fathers |
| flama | flame |
| flamante | brand-new |
| flamenco | flamenco |
| flamenco chileno | Chilean flamingo |
| Flamenco común | Caribbean Flamingo |
| Flamenco del Caribe | Caribbean Flamingo |
| Flammkuchen | Tarte flambée |
| flan | cream |
| flanco | curb |
| Flandes | Flanders |
| Flandes francés | French Flanders |
| Flandes Occidental | West Flanders |
| Flandes Oriental | East Flanders |
| Flandes zelandés | Zeelandic Flanders |
| flanquear | outflank |
| flaquear | droop |
| flaqueza | frailty |
| flaquita | sistergirl |
| flash | flash |
| Flash Gordon | Flash Gordon |
| Flash memory | Flash memory |
| flashcard | flashcard |
| Flashdance | Flashdance |
| Flat assembler | FASM |
| Flat Earth Society | Flat Earth Society |
| Flateyjarbók | Flateyjarbók |
| flato | blasé |
| flatulencia | flatulence |
| flatulente | flatulent |
| flauta | flute |
| Flauta de concierto | Western concert flute |
| flauta de pico | recorder |
| Flauta de tres agujeros | Pipe and Tabor |
| flauta dulce | recorder |
| flauta transversal | flute |
| Flauta traversa | Western concert flute |
| flauta travesera | Western concert flute |
| flautista | piper |
| flautín | piccolo |
| Flavia Pennetta | Flavia Pennetta |
| Flavia Serena | Serena |
| Flavio | Flavius |
| Flavio Arriano | Arrian |
| Flavio Biondo | Flavio Biondo |
| Flavio Briatore | Flavio Briatore |
| Flavio Castino | Castinus |
| Flavio Cresconio Coripo | Flavius Cresconius Corippus |
| Flavio Eugenio | Eugenius |
| Flavio Honorio | Honorius |
| Flavio Josefo | Josephus |
| Flavio Orestes | Flavius Orestes |
| Flavio Teodosio | Count Theodosius |
| Flavio Víctor | Flavius Victor |
| Flavín adenín dinucleótido | FAD |
| Flavín mononucleótido | Flavin mononucleotide |
| Flawil | Flawil |
| Flay Allster | Flay Allster |
| FLCL | FLCL |
| Flea | Flea |
| flebitis | phlebitis |
| flebotomía | bloodletting |
| flecha | arrow |
| Flecha del tiempo | Arrow of time |
| Flecha rota | Broken Arrow |
| Flecha Valona | Flèche Wallonne |
| Flecha Verde | Green Arrow |
| Flechas plateadas | Silver Arrows |
| flechera | archer |
| flechero | archer |
| Flegetonte | Phlegethon |
| Flegias | Phlegyas |
| Fleischer | Fleischer |
| Fleischer Studios | Fleischer Studios |
| flema | phlegm |
| flemon | abscess |
| flemático | cool |
| flemón | abscess |
| Flensburg | Flensburg |
| Flerden | Flerden |
| Flesinga | Flushing |
| fletamento | affreightment |
| fletar | charter |
| Fletcher Henderson | Fletcher Henderson |
| flete | cargo |
| Flevolanda | Flevoland |
| Flexi | Flexi disc |
| flexibilidad | adaptability |
| Flexibilizacíon | Suppling up |
| flexible | flexible |
| flexitarianismo | flexitarianism |
| flexión de brazos | push-up |
| flexografía | flexography |
| Flight simulator x | Microsoft Flight Simulator X |
| Flims | Flims |
| Flip Skateboards | Flip Skateboards |
| flirt | flirt |
| flirtear | flirt |
| flirteo | dalliance |
| Flitro de coseno alzado | Raised-cosine filter |
| Fliunte | Phlius |
| floculación | flocculation |
| floculadores | flocculant |
| Flodoardo | Flodoard |
| flojamente | loosely |
| flojedad | debility |
| flojera | slack |
| flojo | baggy |
