Na-adjective (keiyodoshi), Noun which may take the genitive case particle 'no'
1. crushed flat; flattened; squashed; flat-toppedOnomatopoeic or mimetic word
Noun
2. flat-chested girl; flat chested girlColloquial, Manga slang
Noun
3. sound of a sticky rice cake sticking to somethingOnomatopoeic or mimetic word
Other forms
ペッタンコ、ぺたんこ、ペタンコ、ぺちゃんこ、ペチャンコ、ぺしゃんこ、ペシャンコ、ぺっちゃんこ、ペッチャンコ