From English 'hour'. Used for a period of one hour (often in names such as 'happy hour') or to refer to a one-hour time slot.
今日のライブは2アワーの予定です。
Today's concert is scheduled for two hours.
居酒屋のハッピーアワーでドリンクが半額になった。
Drinks were half-price during the izakaya's happy hour.
アワーごとに料金が変わるプランに加入した。
I signed up for a plan where the fee changes by the hour.