J3, J03, J 3 or J-3 may refer to:

• County Route J3 (California)
• Malaysia Federal Route J3

• Junsen type submarine
• HMAS J3, an Australian submarine

• Junkers J 3, a German Junkers aircraft
• J-3, a U.S. Navy airship
• Piper J-3, a 1938 light aircraft

• J3 perturbation, gravitational force caused by an imperfect symmetry north–south of an object being orbited
• J3 Operations Directorate, part of the US Joint Chiefs of Staff
• GS&WR Class J3, an Irish steam locomotive
• JAC J3, a subcompact car produced by JAC Motors
• Janko group J3, in mathematics
• Eupheme (temporarily designated S/2003 J 3), a satellite of Jupiter
• J3 League, Japanese football league
• Northwestern Air IATA code
• J03: acute tonsillitis ICD-10 code
• Triangular cupola, Johnson Solid number 3
• Samsung Galaxy J3, a smartphone by Samsung
• J3 battlecruiser, a British military vessel design from 1920s
• LNER Class J3, a class of British steam locomotives

Topics referred to by the same term

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