有害

• Reading: ゆうがい
• Romaji: yuugai
• Kanji breakdown: 有 (yuu) — have, exist, possess; 害 (gai) — harm, damage, injury
• Pronunciation: /jɯː.gai/

Meaning

Harmful; hazardous; noxious. Having a negative effect on health, safety, or the environment.

A na-adjective and noun meaning harmful or injurious. The opposite of 有益 (yuueki, beneficial). Very common in environmental, health, and safety contexts. Forms compounds like 有害物質 (yuugai busshitsu, harmful substance) and 有害廃棄物 (yuugai haikibutsu, hazardous waste). Used with な before nouns: 有害な影響 (yuugai na eikyou, harmful influence).

Examples

1. この化学物質は人体に有害だ。 This chemical substance is harmful to the human body.
2. 有害なガスが工場から排出されている。 Harmful gases are being emitted from the factory.
3. 子どもに有害なコンテンツを制限する法律がある。 There are laws restricting content that is harmful to children.

Usage Guide

Context: environment, health, safety regulations

Tone: neutral

Origin & History

From Sino-Japanese: 有 (yuu, have/exist) + 害 (gai, harm/damage). Literally 'having harm' — possessing the quality of causing damage.

Cultural Context

Era: Modern

Generation: All ages

Social background: Universal