Frequency: The word is one of the 3000 most common words in English.
If you describe something as ~, you mean it is extremely important.
He had administrators under him but took the ~ decisions himself...
Improved consumer confidence is ~ to an economic recovery.
= critical
ADJ: oft ADJ to n
~ly
Chewing properly is ~ly important...
Crucially, though, it failed to secure the backing of the banks.
ADV