Mister/ˈmɪstər/ Definition 1 of 3Pro Tip 1/3Respectful Address Use 'mister' to show respect, often when you don't know the person's name. 'Thank you, mister, for holding the door.' Pro Tip 2/3Casual Interactions 'Mister' can make a conversation sound more casual and approachable. 'Hey mister, could you pass the ball back?' Pro Tip 3/3Attention Grabber Starting a sentence with 'mister' grabs attention in public places. 'Mister, you dropped your wallet!'