'窄门' (zhǎi mén) literally means 'narrow gate' — combining 窄 (zhǎi), meaning 'narrow' or 'tight', and 门 (mén), meaning 'gate' or 'door'. Historically, it originates from the biblical phrase 'the narrow gate' (Matthew 7:13–14), symbolizing a difficult, disciplined, or morally demanding path that leads to fulfillment or success. In modern Chinese, it’s used metaphorically to describe any challenging, selective, or highly competitive route — such as elite academic programs, prestigious job markets, or rigorous personal disciplines.

The term carries connotations of scarcity, high standards, and conscious sacrifice. It’s often contrasted with '宽门' (kuān mén, 'wide gate'), implying an easy but ultimately less rewarding path. While rooted in religious imagery, 窄门 is now secularized and commonly heard in education, career, and self-improvement discourse — for example, describing the gaokao as a 'narrow gate' to top universities.