Go hot and cold Definition 1 of 2Pro Tip 1/3Mood Swings Used to describe sudden shifts in someone's emotions or opinions. He goes hot and cold on his commitment to the project every few days. Pro Tip 2/3Uncertainty Shows someone's indecision or unpredictable behavior regarding a specific matter. I'm going hot and cold over the decision to move abroad. Pro Tip 3/3Romantic Hesitation Often used when someone is uncertain about their feelings in a romantic relationship. Julia went hot and cold about going on a date with Tom.