noun which may take the genitive case particle 'no', noun
plain; solid color; patternless
Describes fabric, paper, or surfaces without a pattern, print, or design; often used for clothing, wrapping, or backgrounds.
無地のシャツを着てきた。
I wore a plain shirt.
I prefer plain wrapping paper.
I'm looking for a plain T-shirt.
This handkerchief is plain, with no pattern.
When I made the wall a plain color, the room looked brighter.