To work together or collaborate on something; a dialectal or archaic term for joint effort or cooperation.
From con- (together) plus jobble, possibly related to 'job' or dialectal forms. This appears to be a rare or regional British word, possibly obsolete or surviving in limited dialects.
Rare words like conjobble remind us that English once had far more vocabulary for everyday cooperation—we've lost terms for simple human activities as our language consolidated.
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