'Tī yá' literally means 'to pick (剔) the teeth (牙)' — it refers to the act of removing food particles stuck between teeth, usually with a toothpick, fingernail, or other small tool. The character 剔 conveys the idea of 'removing' or 'extracting' something unwanted, while 牙 simply means 'tooth'. Together, they form a common, colloquial verb describing a routine post-meal hygiene habit.

This action is widely observed across Chinese-speaking communities and often appears in informal speech, literature, or observational humor. While not medically recommended as a primary oral care method (dentists prefer floss), it remains culturally familiar and socially neutral in everyday contexts — though doing it openly at the dinner table may be considered slightly impolite depending on setting and company.