Definitions for drawdownˈdrɔˌdaʊn. Here are all the possible meanings and translations of the word drawdown. Wiktionary(0.00 / 0 votes)Rate this definition: drawdown(Noun) The act of reduction or depletion. drawdown(Noun) The result of reduction or depletion. drawdown(Noun) A change in hydraulic head in a well or other body of water.