耐心 (nài xīn) means 'patient' (adjective) or 'patience' (noun) – the quality of staying calm and not getting annoyed when waiting or dealing with difficulties. It is different from 忍耐 (rěn nài), which is a verb meaning 'to endure or restrain oneself', and from 毅力 (yì lì), which is 'perseverance' or 'willpower'. Note: 病人 (bìng rén) and 患者 (huàn zhě) mean 'patient' as in a sick person, not the same as 耐心.