To firmly maintain one's viewpoint, principles, or situation; to refuse to change one's practices or plans.(verb)
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Use "hold the line" in a sentence
"Page 125 had held on until they had fired their last round, and each time help came to hold the line of battle until we could fill our cartridge-boxes again, and the battle ended at dark."
"He had given Budënny nearly a million men; it was not unreasonable to expect this force, even if it could not hold the line of the Dnieper, to give such an account of itself that the German attack might be blunted — for that summer, at least."
"In utmost haste Pickett replied that a countermand had been sent and Johnson was to hold the line of Swift Creek if it was true, as reported, that the Federals were advancing on that position.27"