In the quinoline fused-ring system of the title compound, C9H9NO, the pyridine ring is planar to within 0.011 (3) Å, while the partially saturated cyclohexene ring adopts a sofa conformation with an asymmetry parameter ΔC
s(C6) = 1.5 (4)°. There are no classical hydrogen bonds in the crystal structure. Molecules form molecular layers parallel to (100) with a distance between the layers of a/2 = 3.468 Å
