A very large-magnitude earthquake. Often accompanied by severe shaking and extensive damage; used in disaster reports and preparedness discussions.
専門家は30年以内に大地震が起きる可能性が高いと警告した。
Experts warned there is a high possibility of a major earthquake occurring within 30 years.
大地震に備えて、非常用持ち出し袋を用意しておこう。
Prepare an emergency kit in case of a major earthquake.
テレビは大地震の速報を伝え、避難を呼びかけた。
The TV reported breaking news of a major earthquake and urged people to evacuate.