Card/kɑːrd/ Definition 1 of 4Pro Tip 1/3Cultural Variations Cards like business cards may have different formats and importance across cultures. In Japan, exchanging business cards is a formal ritual. Pro Tip 2/3Physical Object 'Card' often implies something tangible that can be physically exchanged. Remember to bring your ID card to the test. Pro Tip 3/3Information Storage Cards usually store important information and are kept for reference. The emergency hotline is on the back of your insurance card.