Glossary of terms related to Gulf Coast oil spill

Efforts to stop the Gulf Coast oil spill have given Americans a dizzying array of new technical terms to master. Many of these phrases sound peculiar to ears hearing them for the first time, but their functions are as serious as . . . a failed deadman switch. Below, a list of some of the least intuitive phrases, what they sound like they might mean -- and what they actually do. If they do what they are supposed to do.

Blowout preventor

Sounds like: Someone who took the last appointment at your salon.

Definition: A large valve at the top of an oil well that can be closed if a drilling crew loses control of it but that failed at Deepwater Horizon. (Source: Schlumberger's Oilfield glossary)

Shear rams

Sounds like: Tops the to-do list of a New Zealand shepherd.

Definition: Hardened steel blades within the blowout preventor designed to cut the drill pipe as a last resort to regain control of a well but that failed at Deepwater Horizon.

Deadman switch

Sounds like: When the gravediggers get it wrong.

Definition: An automated mode function failsafe that failed at Deepwater Horizon.

Acoustic trigger

Sounds like: A recurring and irksome sound that works your last nerve.