界定 / 定义为【jièdìng / dìngyì wéi】

界定为 and 定义为 state how a term is being defined, "define X as Y". The term usually comes after 把, and the definition after 为wéi. Both are written: research papers, laws, reports.

With 被 the term becomes the subject. In formal writing 将 often replaces 把.

界定 or 定义

定义 gives a term its meaning. 界定 draws a boundary: what counts and what doesn't. That is why 界定 also takes 范围, 界限, 责任 or 标准 as its object, and why "hard to define" is usually 很难界定.

定义 is also the everyday noun "definition", and the set phrase for giving one is 下定义.

Mistakes

• × 把青年定义十八到三十五岁的人 → 把青年定义为十八到三十五岁的人
• × 给这个词下界定 → 给这个词下定义