Tick away
Definition 1 of 1
Pro Tip 1/3Temporal Imagery
Imagine a clock ticking to feel the slow, unstoppable passage of time represented by 'tick away.' 
The classroom was silent as the minutes ticked away before the exam started.
Pro Tip 2/3Awaiting Events
Use 'tick away' when waiting for an event, emphasizing the feeling of time moving slowly. 
We watched the clock as the seconds ticked away until the new year.
Pro Tip 3/3Tension Building
'Tick away' can express tension or urgency as time runs out for a certain task. 
She could hear the deadline ticking away as she hurried to finish her article.