Definition of Federal question jurisdiction
Cases arising under Constitution of United States, Acts of Congress, or treaties, and involving their interpretation and application, and of which jurisdiction is given to federal courts, are commonly described as involving a "federal question.” See U.S.Const., Art. Ill, Sec. 2, and 28 U.S.C.A. § 1331 with respect to "federal question” jurisdiction of federal courts.
That's the definition of Federal question jurisdiction in Black's Law Dictionary 6th Edition. Courtesy of Cekhukum.com.