Simple past tense and past participle of concuss.(verb)
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Use "concussed" in a sentence
"Craig had no further opportunity for discussing the matter, for the next morning he was "concussed" in midair and retained sufficient sense to bring his machine to the ground."
"Promising No 8 Chris Lowrey damaged knee ligaments and is out for the season while Josh Blackie twisted his knee and Justin Collins was concussed, meaning both will miss the next match."
"And he’s concussed, meaning that he’s had a nasty crack on the skull as well."