A person who works slowly, making a great effort with little result.(noun)
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Use "plodder" in a sentence
"He was what you might call a plodder -- you might call him that."
"He was a kind of plodder, though, good fellow as he was."
"The difference between him, that plodder, and me, the brilliant multi-tasker, is that I might have looked busier as I frantically shuffled through papers and tapped computer keys and shouted into my cell phone."