The increase or buildup of a country's or organization's weapons and military forces, expanding armaments or military capabilities.
政府は近隣諸国の軍備拡大を受けて、防衛費を増額した。
The government increased the defense budget in response to the neighboring countries' arms buildup.
軍備拡大は地域の緊張を高めることが多い。
An arms buildup often raises regional tensions.
メディアはその国の急速な軍備拡大を報じた。
The media reported on that country's rapid arms buildup.