F21 or F-21 may refer to:
Aviation F 21 Luleå, a Swedish Air Force wing IAI F-21 Kfir, a 1973 Israeli-built all-weather, multi-role combat aircraft Lockheed Martin F-21, a variant of the F-16 designed for the Indian Air Force KAI KF-21 Boramae, a South Korean/Indonesian stealth fighter currently under development Farman F.21 Moustique II, a French interwar airplane Taylorcraft F-21, an American light aircraft
Nautical F21 (torpedo), a torpedo developed for the French Navy , an Italian Regia Marina (Royal Navy) submarine in commission from 1918 to 1930 , a 1937 British Royal Navy Tribal-class destroyer , a Venezuelan navy frigate , an Indian Navy Godavari-class frigate , a Taiwanese navy destroyer
Land transport F-21 (Michigan county highway) BMW Series 1, that had a model code called "F21"
Other uses Schizotypal personality disorder, whose ICD-10 code is "F21" Fluorine-21 (F-21 or 21F), an isotope of fluorine Forever 21
See also
Shenyang J-21, 5th generation fighter, also referred to as the "F-21"
21 (disambiguation)