well-known or well known
- Thread starter Tallent
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I'm looking this up, I think the hyphen belongs. I just want to validate this before I say that it is needed. 
It's well known how I cheat and often consult my well-known Webster.
Webster's New World Dictionary makes the miniscule distinction above, so your example would be okay without the hyphen, though I doubt that most editors would reject your manuscript if presented either way.
Okay I have a site that should help you, and the reason why I said it stays.
When adverbs not ending in -ly are used as compound words in front of a noun, hyphenate. When the combination of words is used after the noun, do not hyphenate.
Examples:The well-known actress accepted her award.
Well is an adverb followed by another descriptive word. They combine to form one idea in front of the noun.
The actress who accepted her award was well known.
Well known follows the noun it describes, so no hyphen is used.
A long-anticipated decision was finally made.
He got a much-needed haircut yesterday.
His haircut was much needed.
This is from: Grammar Book
When adverbs not ending in -ly are used as compound words in front of a noun, hyphenate. When the combination of words is used after the noun, do not hyphenate.
Examples:The well-known actress accepted her award.
Well is an adverb followed by another descriptive word. They combine to form one idea in front of the noun.
The actress who accepted her award was well known.
Well known follows the noun it describes, so no hyphen is used.
A long-anticipated decision was finally made.
He got a much-needed haircut yesterday.
His haircut was much needed.
This is from: Grammar Book
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