The phrase “thick as thieves” is an idiom used to describe a close, secretive, and loyal relationship between two or more people. It suggests that the individuals involved share a deep bond, trust, and possibly even a sense of exclusivity in their interactions.

Origins of “Thick as Thieves”

The phrase dates back to at least the 18th century, with its earliest known usage found in British literature. The word “thick” in this context means close, intimate, or inseparable, rather than its more common meaning of density.

• The term “thick” was historically used to describe strong friendships or close connections, similar to saying “thick with someone.”
• The word “thieves” in the phrase likely comes from the idea that criminals often form tight-knit groups, sharing secrets and trusting each other completely.
• The phrase evolved to describe any strong, trustworthy bond, not just those between criminals.

How “Thick as Thieves” Is Used Today

The phrase is often used in casual conversation to describe friendships, partnerships, or alliances:

• “Those two have been thick as thieves since childhood.” (Meaning they have always been very close friends.)
• “The managers at the company are thick as thieves—they always back each other up.” (Suggesting a strong and possibly exclusive alliance.)
• “She and her sister are thick as thieves, always sharing secrets.” (Indicating a deep trust between them.)

Does “Thick as Thieves” Have a Negative Meaning?

While the phrase originates from the idea of criminals working together, its modern use is not necessarily negative. It usually just means a strong friendship or alliance, though it can imply secrecy, depending on the context.

For example:

• If used to describe business leaders or politicians, it might suggest they are conspiring or making secretive deals.
• If used for friends or family members, it usually means they have a close, loyal relationship.

Conclusion

The phrase “thick as thieves” is a well-known idiom that describes a strong, secretive, and loyal relationship between individuals. Although its origins relate to criminal activity, today it is mostly used to express deep friendships or alliances. Whether positive or slightly suspicious depends entirely on the context in which it is used.