cold feet
The origin and history of cold feet.
Etymology
Idiomatic sense possibly from a calque of German kalte Füße bekommen (“to get cold feet”), or of Lombard avegh minga frecc i pee (“to have no money”, literally “to be cold in the feet”) (Italian aver freddo ai piedi), said by a person who wishes to stop gambling, allegedly because the person now has cold feet due to being too poor to afford proper footwear.