ligroinEtymologyAttested since 1872, borrowed from German Ligroin, a trade mark of illuminating liquid hydrocarbon first attested in 1866 as Lygroin and Ligroine. Further origin uncertain, but possibly from Ancient Greek λιγυρός (ligurós, “clear”).ligroin means A petroleum fraction boiling 75°-125°C used as a solvent and fuel. Lexicurio rates it Sui generis — a strength score of 94 out of 100.nounA petroleum fraction boiling 75°-125°C used as a solvent and fuel.