Learner's definition of GOODNESS
1 : the quality or state of being good: such asa : the quality or state of being kind, honest, generous, helpful, etc.
b : the quality or state of being useful or effective
I believe there is (some) goodness in everyone.
Even if you don't agree, at least have the goodness to be polite!
She agreed to help him out of the goodness of her heart. [=because she is a kind and generous person]
2 — used to express mild surprise or shock
◊ People use I swear to goodness, I hope to goodness, or I wish to goodness to add force to a statement.
Goodness, it's hot out today!
Goodness (only) knows how it happened.
“Did you stop them?” “Goodness (gracious), no!”
Oh, my goodness!
for goodness' sake
— used to express surprise or annoyance