一いっ定てい不ふ変へん

noun

invariable; permanent; constant and unchanging

Describes something that is fixed and does not change over time; often used in formal or written contexts.

• 自し然ぜんの法ほう則そくは一いっ定てい不ふ変へんではない。

  The laws of nature are not invariable.

• 彼かれの信しん念ねんは一いっ定てい不ふ変へんだ。

  His beliefs are constant and unchanging.