Superlative form of gritty: most gritty.(adjective)
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Use "grittiest" in a sentence
"He crafted the Peace Corps at lightening speed by drafting the sharpest, grittiest minds in America onto his staff."
"She adds, "As the grittiest of the 'Trek's, our show's fabric was interwoven with stories of war, family, loyalty, deception, sexuality, and a dash of whimsicality that both took the edge off and served as a mirror.""
"The grittiest trail hoppers will actually put welders on their vehicles for in-field repairs and rack-mounted Jerry cans of fuel and water for those extended trips, postapocalypse."