Mahlzeit!
Mealtime! The greeting colleagues give each other around midday.
Brückentag
Bridge day. A single working day between two days off, such as a public holiday and the weekend. Duden notes that it is especially suited to taking as a day of leave.
Feierabendbier
The beer after the end of the working day.
Work-Life-Balance
The English term is in the Duden as a German noun. It is defined as a balanced relationship between the demands of the job and a person’s private needs.