noun
anti-establishment spirit; defiant opposition mindset
Political term referring to a mindset of defiance or resistance held by those not in power, especially opposition parties. Often used in contexts of political commentary.
彼の演説には強い在野精神が感じられた。
His speech conveyed a strong anti-establishment spirit.
在野精神を失った野党は支持を広げられない。
An opposition party that loses its defiant spirit cannot broaden its support.
反骨精神 is a broader term for a rebellious or nonconformist spirit, not limited to politics. 在野精神 specifically refers to the defiant mindset of those out of power, especially in a political context.
Compound of 在野 (ざいや, 'out of power, not in office') and 精神 (せいしん, 'spirit, mindset'). The exact historical derivation is uncertain, but the term is conventionally associated with political opposition.