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bridge off

1. n. [Well Workover and Intervention]
The accumulation or buildup of material, such as sand, fill or scale, within a wellbore, to the extent that the flow of fluids or passage of tools or downhole equipment is severely obstructed. In extreme cases, the wellbore can become completely plugged or bridged-off, requiring some remedial action before normal circulation or production can be resumed.
Alternate Form: bridge-off