放射能

• Reading: ほうしゃのう
• Romaji: houshanou
• Kanji breakdown: 放 (hou) — emit, release; 射 (sha) — shoot; 能 (nou) — ability, power
• Pronunciation: /hoː.ɕa.noː/

Meaning

Radioactivity; the property of certain substances to emit radiation through nuclear decay.

A noun for the physical phenomenon of radioactive decay. Became widely known in Japan after the atomic bombings and the Fukushima disaster. Distinct from 放射線 (radiation, the rays themselves) and 放射性物質 (radioactive material). Often used in news about nuclear energy and environmental concerns.

Examples

1. 事故後、周辺地域の放射能を測定した。 After the accident, radiation levels in the surrounding area were measured.
2. 放射能汚染の影響は長期間に及ぶ。 The effects of radioactive contamination can last for a long time.
3. 食品の放射能検査が厳しく行われている。 Strict radioactivity testing of food products is being carried out.

Usage Guide

Context: science, news, environment, nuclear energy

Tone: serious

Origin & History

From Sino-Japanese 放 (hou, to emit) + 射 (sha, to shoot) + 能 (nou, ability/power). Literally 'the ability to emit shooting rays,' describing the property of radioactive substances.

Cultural Context

Era: Modern

Generation: All ages

Social background: Universal