You may read the following two texts aloud:
Ich sage dir doch, entgegen aller Behauptungen ist Bob kein Baumeister! Er ist wirklich ein Bauer!
compare it with
Bob ist der Dümmste und erntet die dicksten Kartoffeln. Er ist wirklich ein Bauer!
I think chances are pretty high that you have spelled the first 'wirklich', which means 'in truth', in a different manner than the second one, which means 'to large extent'. At least if you are a German native from the Rhineland-Palatia.
The same can be done if you replace 'wirklich' by 'echt' or 'wahrhaftig'. I believe that English 'really' can be used with two meanings, too, and that both German and English tend to use the same words for both meanings in general. This phenomenon confuses me.
- What is the phonetic difference between the two pronunciations? I would even guess it is tonal, but I don't know.
- Are these pronunciations variants of the same word, or should they be considered two different words?