Disposed or consenting; inclined: willing to go along; cheerfully consenting or ready; done, given, borne, used, etc., with cheerful readiness to be used for holding liquids or other contents or as a tube or duct, as an artery or vein, containing or conveying urine, semen, or some other body fluid.
Primarily used to convey disbelief that one has been "cured" of homosexuality by primarily religious means.
Secondarily used to convey subtle snark in conversation with those who purport to have been "cured" of homosexuality or to have prayed the gay away.
Girl, our new Pastor is born again. He's washed clean of the homosexuality and the gay. That's right. But I hear he's a 'willing vessel' for more than just the word of the Lord, if you know what I'm sayin'.