We have a Japanese Kanji character written as 面, which originally means a mask you place over your face. As it turns out, it's a simple origin once you learn how the character was made. It's from the human face. Let's look at the mask character.
面, read as Men or Omo in Japanese, came from a human face. Please look at my drawing. The initial image shows that a face is surrounds by something or the dotted line on the picture. This represents what you cover with on your face, which might be a mask. This can explain how today's character was created.
As this Kanji is taught in third grade in elementary school, you'll find it's used by various meanings. Since the first definition is a mask, other meanings are 2) face and 3) surface. For the second definition, Senmen (洗面) means you wash your face. And Jimen or 地面 is a ground surface.
Another example I came up with the first is popular children's TV hero called Kamen Rider (仮面ライダー). Kamen literally means a false face or mask. The series has lasted over the years since I was a child. In fact, the latest version named "Kamen rider Fourze (仮面ライダー フォーゼ)" is the anniversary series following 40 years by various Kamen riders. Why we say "rider" is because the superhero appears as he rides on a sleek motorcycle. Every Sunday it starts at 8:30 nationwide. Some call it hero time or time for children because TV broadcasters spare a lot of the morning time for children with cartoons and hero dramas. Especially, eight o'clock every Sunday reminds Japanese parents and their children of Kamen Rider.
If you want to know what Kamen Rider Fourze looks like, here is the advertising on Youtube, which someone posted. The TV program had started since last September.
Youtube ==> 仮面ライダーフォーゼ 新番組予告 (Kamen Ride Fourze -- Promotional video for the new program)
By the way, what do you know Fourze means? I couldn't figure out as it might not be English. If someone knows, please let me know.