'Shuā kǎ' literally combines 'shuā' (to swipe, brush) and 'kǎ' (card), describing the physical action of swiping a magnetic stripe card or tapping a contactless card to authorize a payment or gain access. It is commonly used in everyday transactions — at supermarkets, restaurants, metro gates, or office entry systems — and reflects modern digital lifestyle habits in urban China.

Though originally tied to magnetic cards, the term has expanded colloquially to include contactless 'tap-to-pay' actions using bank cards, transit cards, or even smartphones with NFC enabled. It is neutral in register — appropriate in both spoken and written contexts — and almost always functions as a verb, typically appearing after a subject and before an object (e.g., 'I swipe my card') or as a standalone verb phrase (e.g., 'Please swipe your card').