Simple past tense and past participle of lack.(verb)
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Use "lacked" in a sentence
"On the whole, though, the term lacked drama: no news-cycle-eating cases or base-enflaming confirmation battles to be found."
"The band chose Buffalo Hump to succeed him, but the title lacked any meaning, since from now on the band had no common leader.35 What was left of them found that the buffalo no longer came south to their ranges, and that much of the other game had disappeared, too."
"Ban, in Tokyo on an Asian tour, repeated his view that the violence-marred election that gave veteran leader Robert Mugabe another term lacked legitimacy."