die Zeitverschwendung
waste of time
The use of time for an activity that brings no benefit or meaningful result.
Stundenlang in der Warteschlange zu stehen war die reinste Zeitverschwendung.
Standing in line for hours was a complete waste of time.

waste of time
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waste of time
The use of time for an activity that brings no benefit or meaningful result.
Stundenlang in der Warteschlange zu stehen war die reinste Zeitverschwendung.
Standing in line for hours was a complete waste of time.

The word is made up of 'Zeit' (time) and 'Verschwendung' (waste). 'Verschwendung' comes from the verb 'verschwenden' (to waste). So it literally means that time is being used up uselessly.
Ich finde, stundenlanges Anstehen ist die größte Zeitverschwendung.
I think standing in line for hours is the biggest waste of time.
The noun is a direct derivation from the common verb-noun combination 'Zeit verschwenden' (to waste time). If you want to say what a person is actively doing, use the verb.
Verschwende deine Zeit nicht mit unwichtigen Dingen!
Don't waste your time on unimportant things!
'Zeitverschwendung' (waste of time) is often used with the verb 'sein' (to be) to evaluate an activity. A typical structure is: '[activity] ist (reine) Zeitverschwendung' ([activity] is a complete waste of time).
Den ganzen Tag nur fernzusehen ist für mich Zeitverschwendung.
For me, just watching TV all day is a waste of time.
To express that something is a complete waste of time, the word is often intensified with the adjectives 'rein' (pure) or 'pur' (pure). These combinations are very common.
Das Meeting war die reinste Zeitverschwendung, es wurde nichts entschieden.
The meeting was a complete waste of time; nothing was decided.
pastime
'Zeitverschwendung' and 'Zeitvertreib' both have to do with how you use time. The difference is the evaluation. 'Zeitverschwendung' is negative: you do something that has no benefit or leads to no meaningful result. 'Zeitvertreib' is usually neutral or positive: you occupy yourself pleasantly, especially in your free time or while waiting. The words can be confused because both can describe an activity without an urgent goal. But 'Zeitverschwendung' criticizes the activity, while 'Zeitvertreib' sees it as a normal or pleasant activity.

Dieses lange Meeting war für alle eine Zeitverschwendung.
This long meeting was a waste of time for everyone.
Für Ben ist Schach ein ruhiger Zeitvertreib nach der Arbeit.
For Ben, chess is a quiet pastime after work.