S9

S9 can refer to:

Transportation

• SIAI S.9, a 1918 Italian flying boat
• USS S-9 (SS-114), a 1920 S-class submarine of the United States Navy
• East African Safari Air IATA airline designator
• County Route S9 (California)
• Rans S-9 Chaos, light aerobatic aircraft

Rail

• S9 (Berlin), an S-Bahn line
• S9 (Rhine-Ruhr S-Bahn)
• S9 (Rhine-Main S-Bahn)
• S9 (ZVV), an S-Bahn line in the cantons of Zürich and Zug in Switzerland
• a Stadtbahn Karlsruhe line
• Prussian S 9, a 1908 German steam locomotive class
• Line S9 (Milan suburban railway service)
• Sri Lanka Railways S9, a diesel multiple unit train

Other uses

• S9 (classification), a disability swimming term
• S9 fraction, a postmitochondrial liver fraction
• S9: Keep container in a well-ventilated place, a safety phrase in chemistry
• S9, a district of the S postcode area in Sheffield, England
• Cowon S9, a portable media player
• British NVC community S9, a swamps and tall-herb fens community in the British National Vegetation Classification system
• Motorola S9, a Bluetooth stereo headset
• S9, a termination record in Motorola's SREC (file format)
• S₉, an allotrope of sulfur

See also

• S09, a quantum key distribution protocol
• HMS Oberon (S09), a 1961 British Royal Navy Oberon-class submarine
• Brave Fire S09, an Osamu Tezuka anime