To replenish (a lawn, etc.) by adding more seeds.(verb)
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Use "overseed" in a sentence
"But if you "overseed" -- that is, invest in a broad and integrated portfolio of systems management tools -- you are more likely to have green success with one of them."
"In the summer, I let it go dead, but in the winter, I have a vegetable garden and I overseed with flowers."
"If the soil doesn't freeze where you live, fall is the best time of year to sow seed for a new lawn, to repair bare spots in an old lawn, or to overseed a dormant summer lawn."