DEF: a long period when there is little or no rain.
EX: There is a severe drought in the country, it has not rained in 4 months; trees and animals are dying because there is no water.
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Merriam-Webster Online Dictionary
drought (noun)1.
a period of dryness especially when prolonged , specifically one that causes extensive damage to crops or prevents their successful growth
2.
a prolonged or chronic shortage or lack of something expected or desired