surface; appearances; exterior
Refers to the outward appearance or surface of something, often with a nuance of superficiality or what is visible on the outside.
His kindness might be only on the surface.
Don't judge by appearances alone.
Compound of 上 (うわ, 'upper') and 面 (つら, 'face, surface'). The reading うわつら is a kun'yomi compound.