a long hollow cylinder for carrying a substance (as a liquid or gas) <all of the wiring for the converted residential loft is concealed in a vertical trough> Related Words drain
, waste pipe
a long narrow channel dug in the earth <I slid and fell into the trough by the side of the road, scraping my leg>
a pipe or channel for carrying off water from a roof <the troughs on the eaves of the house were clogged with leaves>
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