An archaic or obsolete term meaning to joust against or collide with; to encounter in combat or confrontation.
From ad- + joust (from Old French joster, of uncertain origin). This is a very rare historical word.
This archaic word is almost forgotten, but it shows that 'joust' (the chivalric combat sport) had a prefix form 'adjoust'—most prefix forms have been lost as languages simplify over centuries.
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