The N atom in the title compound, C19H13NO, lies -0.0365 (14) A from the plane formed by the fluorene system, and the C [symbol: see text] N distance is 1.143 (2) A. The C [symbol: see text] C distance is 1.191 (2) A, and the ethynyl group deviates slightly from linearity, with C-C [symbol: see text] C-C bond angles of 172.0 (1) and 176.1 (2) degrees. Terminal CH2 and CH3 groups are 50:50 disordered, with equal C-C distances of 1.408 (3) and 1.406 (3) A.