sacrificial anode

American  

noun

1. Chemistry.  an anode that is attached to a metal object subject to electrolysis and is decomposed instead of the object.

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sacrificial anode British  

noun

1. metallurgy an electropositive metal, such as zinc, that protects a more important electronegative part by corroding when attacked by electrolytic action

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Etymology

Origin of sacrificial anode

First recorded in 1975–80

Example Sentences

After that brick — known as a sacrificial anode — meets its untimely demise, another is bolted in its place.

From Los Angeles Times

Don�t ignore a scratch and unwittingly let your aluminum outboard motor become a sacrificial anode.

From Time Magazine Archive