This is the 178th most frequent German word.
wirklich
"Really" or "truly."
Usage here: 'wirklich' is used to emphasize the degree of amazement.
Das ist wirklich erstaunlich!
This is really amazing!
Usage here: 'wirklich' is used to express disbelief or confirmation of an action.
Hast du wirklich den ganzen Kuchen gegessen?
Did you really eat the whole cake?
Usage here: 'wirklich' is used to add sincerity or intensity to the speaker's uncertainty.