1 definition by BoarHog

phrase describing a close personal bond between two or more people or inseparable friends

(suggests that those who are thicker than thieves will not forsake or betray any of the others)
Person 1:
Those boys have known each other since they were toddlers.

Person 2:
Yep, they're thicker than thieves.
by BoarHog December 7, 2010
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