The story
- Dutch · borrowed fromklare lijn“clear line”
- French · borrowed fromligne claire“clear line”
- English todayligne claire
From French ligne claire (“clear line”), originally from Dutch klare lijn (“clear line”), originally coined by Dutch artist Joost Swarte in 1977 to describe the work of Belgian artist Hergé.
Etymology from Wiktionary, CC BY-SA 4.0.