A crystalline tricyclic aromatic hydrocarbon obtained from coal tar and used as a precursor for dyes, pigments, and pharmaceuticals.
Fluorene consists of two benzene rings fused to a cyclopentane ring. Systematic name: o-biphenylenemethane; C₁₃H₁₀.
Mid 19th century; earliest use found in American Journal of Science. From fluoro- + -ene, after French fluorène, named for the violet fluorescence of its crystals.