FLT
- Alovudine
- FTL (disambiguation)
- Fairlight (group)
- Fermat's Last Theorem
- Fermat's little theorem
- Finger Lakes Trail
- Finite Legendre transform
- Flight Centre
- Flitwick railway station
- Fluorothymidine F-18
- Flutter-tonguing
- Foreign Language Teaching
- Free Federation of Workers
- Liberation Front of Chad
- Luxembourg Tennis Federation
- Phaeton Airport