Plain-English definition
Chains do not naturally talk to each other. A bridge lets value cross from one to another, usually by locking the asset on one side and minting a representation on the other.
Bridges concentrate a lot of value in one place, which has made them among the most attacked pieces of infrastructure in crypto. The depth on each side, and who controls the lock, are the things worth checking.
Why it matters
Bridge matters because crypto markets can look precise while still being shallow, crowded, or poorly sourced. A useful read is not just the number. It is the number, the size behind it, the context around it, and the part it cannot explain.
Simple example
A simple Bridge example is a reader comparing two venues with the same headline price but different depth. The deeper venue can absorb more capital before the trade, peg, or yield reading starts to move against the user.
How Bathymark uses this term
Bathymark uses Bridge to translate open market data into live liquidity readings. When the term touches a live page, the reading links back to the relevant chain, protocol, stablecoin, DEX, perps, or Signal so the source remains checkable.
Common mistake
The common mistake is treating Bridge as a complete signal by itself. Bathymark treats it as one instrument: useful when read beside liquidity, source, size, and what the number cannot prove.