also: のっぺらぽう · のっぺらぼー · ぬっぺらぼう
noun which may take the genitive case particle 'no', na-adjective, noun
flat and smooth; featureless
Describes a surface or object that is completely flat and smooth, lacking any irregularities or distinguishing features.
のっぺら坊な壁には何も飾られていなかった。
The flat, featureless wall had nothing hanging on it.
noun which may take the genitive case particle 'no', na-adjective, noun
unchanging; monotonous; expressionless
Used for things that lack variation or character, such as a monotonous landscape, an expressionless face, or a dull routine.
彼ののっぺら坊な表情からは何も読み取れなかった。
I couldn't read anything from his expressionless face.
この辺りはのっぺら坊な田園風景が続いている。
Around here, a monotonous rural landscape stretches on.
noun
noppera-bō; faceless ghost
In Japanese folklore, a yōkai that appears as a human but has a completely smooth, featureless face. Often used to scare people.
のっぺら坊は、顔のない妖怪として知られている。
The noppera-bō is known as a faceless yōkai.