Tonight/təˈnaɪt/ Definition 1 of 2Pro Tip 1/3Time Specificity Use 'tonight' to refer to the evening or night of the current day only. Are we still on for our game night tonight? Pro Tip 2/3Casual Plans 'Tonight' is often used when talking about social plans or casual meetups. Let's catch up tonight over coffee. Pro Tip 3/3Immediate Future It's used for something happening in the immediate future but doesn't imply an exact time. I'll start packing for our trip tonight.