noun
young woman who acts like an old man
Slang term for a young woman who adopts stereotypical middle-aged man behaviors, such as using rough language, drinking, or having old-fashioned tastes.
彼女はオヤジギャルで、いつも居酒屋で焼き鳥を食べながら愚痴をこぼしている。
She's an oyaji-gal, always grumbling over yakitori at the izakaya.