Frequency: The word is one of the 1500 most common words in English.
1.
Knowledge is information and understanding about a subject which a person has, or which all people have.
She told Parliament she had no ~ of the affair.
...the quest for scientific ~.
N-UNCOUNT: usu with supp
2.
If you say that something is true to your ~ or to the best of your ~, you mean that you believe it to be true but it is possible that you do not know all the facts.
Alec never carried a gun to my ~...
PHRASE: PHR with cl/group
3.
If you do something safe in the ~ that something else is the case, you do the first thing confidently because you are sure of the second thing. (WRITTEN)
You can let your kids play here, safe in the ~ that they won’t get sunburn.
PHRASE: PHR after v, usu PHR that