noun
rebellious spirit; defiant attitude
Describes a strong inner disposition to resist authority, convention, or control; often used positively for independent-minded people.
彼は反骨精神にあふれた若者だ。
He is a young man full of rebellious spirit.
その作家の作品には反骨の姿勢が表れている。
The writer's works show a defiant attitude.
Compound of 反 (anti-, against) and 骨 (bone, frame), literally 'anti-bone' or 'against the frame', suggesting a spirit that goes against the established structure. The exact historical derivation is uncertain, but the kanji combination is conventionally associated with a rebellious disposition.