立志 means 'to resolve' or 'to make a firm aspiration' — it expresses the act of setting a serious, long-term goal, often tied to personal growth, moral development, or life purpose. The character 立 (lì) means 'to stand' or 'to establish', suggesting something being firmly set in place; 志 (zhì) means 'will', 'aspiration', or 'ambition', referring to one's inner determination. Together, they convey the idea of 'standing firm in one's aspiration' — not just wishing, but committing with sincerity and resolve.

This word is commonly used in formal, inspirational, or educational contexts — such as speeches, essays, or advice from elders. It carries a dignified, earnest tone and often appears in classical or modern literary Chinese. While similar to everyday words like 决定 (juédìng, 'to decide'), 立志 implies deeper conviction and moral weight, frequently linked to ideals like serving society, pursuing knowledge, or cultivating virtue.