Simple past tense and past participle of irrigate.(verb)
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Use "irrigated" in a sentence
"This is an area which will be irrigated from the Indus River."
"Albracht won the 2005 National Corn Yield Contest in the "irrigated" category, producing a whopping 352 bushels per acre."
"As I wrote, I had understood that non-wilderness rural areas such as irrigated fields, although cooler than pavement, were still warmer than actual wilderness."