The word "clair" means clear or clearness in French. It is often used to describe something that is easy to understand, see, or perceive. Full definition
What is striking is that, although in theory the formulation of the acte clair doctrine by the ECJ is extremely strict, in practice the Court has been very flexible when applying the different criteria. (europeanlawblog.eu)
HOW DOES DRIVING SCHOOL IN SAINT CLAIR SHORES MICHIGAN WORK? (drivinguniversity.com)
In that case, the acte clair doctrine does not hold, and the court of last instance is under an obligation to refer a question. (leidenlawblog.nl)