蔓延
mànyán · HSK 7
spread out
🌿 蔓 = creeping vine + 延 = extend; vines spread and extend everywhere
蔓 (màn) is a creeping vine or tendril; 延 (yán) means to extend or prolong. Together they describe how something creeps outward and extends like a vine taking over ground, hence to spread out.
延 — 廴 (long stride) + 㥯/丿 + 止 (foot)
延 originally depicted a foot (止) on a road or path (廴), suggesting walking a long way. From this came the meanings 'to extend,' 'to prolong,' and 'to delay.' The modern form retains 廴 on the left as the semantic clue for movement and extension.