1.
vacuum
A space entirely devoid of matter, or a space with greatly reduced air pressure.
宇宙は真空の状態だ。
Space is in a vacuum state.
真空パックで食品を保存する。
I preserve food in vacuum packs.
真空パック is a common compound
真空状態では音が伝わらない。
Sound doesn't travel in a vacuum.
COMMON COMPOUNDS:
- 真空パック (vacuum pack/packaging)
- 真空管 (vacuum tube)
- 真空掃除機 (vacuum cleaner) - though this is different from scientific vacuum
- 真空状態 (vacuum state/condition)
SCIENTIFIC NOTE:
In physics, a "perfect vacuum" is theoretical. In everyday use, 真空 often refers to low-pressure environments or vacuum packaging for food preservation.
[Register: Neutral to Technical]