noun🔗ShareA line formed by the surface of the water on the hull of a ship when she is afloat; any of a series of short lines marked on the hull to show where the waterline would be under different loadings."The small boat had a dirty waterline, showing how high the water level had been when it was fully loaded. "nauticalvehiclesailingoceanmarktechnicalChat with AIVocabulary GamePractice Reading
noun🔗ShareA horizontal line indicating the shape of an airfoil."The engineer carefully studied the waterline on the airfoil model to understand how the wing would perform in flight. "technicalnauticalvehicleChat with AIVocabulary GamePractice Reading
noun🔗ShareA line showing where the water has been, usually a line separating dry land and wet areas; a watermark or tidemark."After the heavy rain, a dark waterline was visible on the garage wall, showing how high the water had risen. "nauticalenvironmentmarkgeographyoceanChat with AIVocabulary GamePractice Reading
noun🔗ShareThe inner rim of the eyelid, just behind the lash line; primarily used in reference to the application of eyeliner."She applied the eyeliner carefully to her waterline for a more dramatic look. "anatomyappearancebodypartChat with AIVocabulary GamePractice Reading
