幸存 (xìng cún) means 'to survive (a disaster)' with a strong emphasis on luck — the 幸 (xìng) component means 'fortune'. It's more specific than 生存 (shēng cún 'to exist/survive in general') and 存活 (cún huó 'to remain alive'), as 幸存 always implies escaping a specific calamity. 幸免 (xìng miǎn) is similar but focuses on 'narrowly avoiding' the disaster itself rather than staying alive afterward.