Shirt/ʃɜːrt/ Definition 1 of 4Pro Tip 1/3Formal Settings Shirts with collars are preferred in business or formal events. He chose a crisp, button-down shirt for the interview. Pro Tip 2/3Casual Variations T-shirts and polo shirts are more casual and typically worn in relaxed settings. On weekends, he switched to a comfy t-shirt. Pro Tip 3/3Cultural Connotations In some cultures, a white shirt signifies purity or formality. The groom wore a white shirt symbolizing purity.