油灯 (yóu dēng) literally means 'oil lamp' — a traditional lighting device that burns oil (usually vegetable or animal oil) with a wick inside a small container. The character 油 means 'oil', and 灯 means 'lamp' or 'light'; together, they form a compound noun referring specifically to pre-electricity lamps common in rural China and historical settings. Oil lamps were widely used before modern electricity became widespread, especially in homes, temples, and during festivals.

Today, 油灯 is rarely used for daily lighting but appears frequently in literature, historical dramas, museum exhibits, and poetic or nostalgic contexts. It often symbolizes simplicity, tradition, or the past — for example, describing a quiet countryside scene at night or evoking memories of childhood in older generations. While modern LED lights have replaced it functionally, the term remains culturally resonant and is understood by all native speakers.