The time period (rush hour) when roads and public transport are especially crowded, typically due to commuting.
朝のラッシュアワーで電車がとても混んでいたため、一本遅らせて乗った。
The train was very crowded during the morning rush hour, so I took a later one.
ラッシュアワーを避けて早めに出社するようにしている。
I try to go to work earlier to avoid the rush hour.
ラッシュアワーの道路は渋滞がひどく、タクシーでも時間がかかる。
Roads during rush hour have severe traffic jams, so even taking a taxi takes a long time.