Per diem

[Sarah]

By the day; substantively (chiefly U. S.), an allowance oramount of so much by the day.

[Michiko]

a [daily] [allowance], a daily [fee]

[Kit]

Money that your employer grants you will traveling so you can drink alcohol [liberally]. [Employers] province this [entitlement] to relieve stress derived from travel, bosses, co-workers, etc.