Correct the wheel alignment on a car.
An example of to correct is a piano teacher showing his student which keys are right in order to make the sound for which the teacher was hoping.
An example of to correct is a third grade teacher marking the words that were not spelled right on a spelling test.
An example of correct used as an adjective is the phrase "correct procedure," such as baking a cheese cake in a springform pan is the correct procedure.
Correcting for the effects of air resistance.
The new glasses corrected his blurry vision.
He corrected the position of the book on the mantle.
Origin of correct
From American Heritage Dictionary of the English Language, 5th Edition