1.
If something lends or gives ~ to a theory or story, it makes it easier to believe. (FORMAL)
Good studies are needed to lend ~ to the notion that genuine progress can be made in this important field.
= credibility
N-UNCOUNT
2.
If you give ~ to a theory or story, you believe it. (FORMAL)
You’re surely not giving any ~ to this story of Hythe’s?
N-UNCOUNT