遇难 is formed by combining the character 遇, meaning 'to encounter,' which is constructed from the radical 辶, indicating movement, and the component 禺, primarily serving as a phonetic element, with the character 难, meaning 'disaster' or 'calamity,' itself composed of 又 and 隹. Together, they create a compound where 遇 conveys the action of meeting and 难 specifies the adverse event, resulting in the literal meaning 'to encounter disaster,' specifically used to refer to perishing in an accident or tragic circumstance.