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dilapidate [dilapidate 词源字典]: dilapidate: [16] It is a common misconception that dilapidate means literally ‘fall apart stone by stone’, since the word comes ultimately from Latin lapis ‘stone’ (as in lapis lazuli [14], literally ‘azure stone’). But in fact Latin dīlapidāre meant ‘squander’ (a sense once current in English, but now superseded). It was a compound verb formed from the prefix dis- ‘apart’ and lapidāre ‘throw stones’, and thus originally must have meant literally ‘scatter like stones’, but its only recorded sense is the metaphorical extension ‘throw away or destroy wantonly, squander’.

The application of the word to the destruction of buildings is a piece of later etymologizing.
=> lapis lazuli[dilapidate etymology, dilapidate origin, 英语词源]
dilapidate (v.): 1560s, "to bring a building to ruin," from Latin dilapidatus, past participle of dilapidare "to squander, waste," originally "to throw stones, scatter like stones;" see dilapidation. Perhaps the English word is a back-formation from dilapidation.
dilapidated (adj.): "in ruins, broken down," 1806, past participle adjective from dilapidate.