信心 (xìn xīn) is a compound noun meaning 'confidence' or 'faith' — the belief in one's own ability, in others, or in a positive outcome. It combines 信 (xìn), meaning 'to trust' or 'belief', and 心 (xīn), meaning 'heart' or 'mind'. Together, they convey an inner, heartfelt conviction — not just intellectual assurance, but emotional and psychological certainty rooted in the heart-mind.

This word is commonly used in personal, academic, professional, and social contexts: students build 信心 through practice; leaders inspire 信心 in their teams; doctors help patients regain 信心 after illness. It often appears with verbs like 有 (yǒu, 'to have'), 缺乏 (quēfá, 'to lack'), 增强 (zēngqiáng, 'to strengthen'), or 失去 (shīqù, 'to lose'). Unlike the English 'confidence', 信心 rarely refers to outward self-assurance alone — it emphasizes internal trust, sincerity, and resilience.