Champing at the bit
Definition 1 of 1
Pro Tip 1/3Eagerness Intensity
The phrase often suggests strong excitement or an almost uncontrollable desire. 
Fans were champing at the bit as the concert tickets went on sale.
Pro Tip 2/3Metaphoric Origin
'Champing at the bit' originates from horses biting their bits eagerly when impatient to start. 
She's been champing at the bit for her chance to speak at the conference.
Pro Tip 3/3Casual Style
It's an informal phrase best used in casual conversation or creative writing. 
He's been champing at the bit to show you his new bike.