Sue Novak of the Idea Chemist pointed out this headline today.
Staunch can mean several things, none of which apply in this headline: steadfast, strong, faithful, substantial. It can also mean watertight.
All of those meanings are adjectives.
The word the headline writer wanted was stanch, a verb meaning to stop the flow of.
As the headline shows, the distinction between the two words has been fading, no doubt because of misuse. American Heritage lists staunch and stanch as alternative spellings of each other.
The AP Stylebook and the New York Times stylebook, among others, maintain the distinction.
Interestingly, stanch is the older word, but staunch is by far the more common word today. (In a Google search, staunch produced four times more hits than stanch. And as you can see in the examples at right, staunch was misused frequently in headlines about the recent oil well debacle in the Gulf of Mexico.)
As with so many homophones, there’s no easy way to remember the difference between the two words. (At least that I know of.)
My advice: Be aware. When you use one or the other, look it up.