This is the 11524th most frequent German word.
steffi
"Steffi" is a diminutive form of the German name "Stefanie," equivalent to "Stephanie" in English.
The word 'Steffi' is used here as a proper noun, serving as the name of the subject of the sentence.
Steffi ist eine hervorragende Tennisspielerin.
Steffi is an excellent tennis player.
In this sentence, 'Steffi' again appears as a proper noun, referring to a specific individual known to both the speaker and the listener.
Ich habe erfahren, dass Steffi heute nicht zur Arbeit kommen wird.
I found out that Steffi will not come to work today.
Here, 'Steffi' is once again a proper noun, used as the object to whom the action of congratulating is directed.