Describing something that has, or is in process, of decaying.(adjective)
Simple past tense and past participle of decay.(verb)
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Use "decayed" in a sentence
"Whoever enquires, as I have frequently done, from those who have asked me an alms; what was their former course of life, will find them to have been servants in good families, broken tradesmen, labourers, cottagers, and what they call decayed house-keepers; but (to use their own cant) reduced by losses and crosses, by which nothing can be understood but idleness and vice."
"My reading has steadily decayed from the start of the year (which I think is mostly due to travel more than anything else):"
"Unlike U.S. cities, which have decayed from the center outward, Johannesburg is ringed by its destitute areas-a condition the South African economist Richard Tomlinson likens to a "too-tight belt around a very fat stomach.""