This is the 15178th most frequent German word.
telefonisch
"Telefonisch" means "by telephone" or "over the phone."
The word 'telefonisch' in this sentence means 'via telephone,' indicating the method of confirmation.
Wir haben die Reservierung telefonisch bestätigt.
We confirmed the reservation via telephone.
Here, 'telefonisch' is used to specify the preferred means of communication: by telephone.
Er bevorzugt es, telefonisch Kontakt aufzunehmen.
He prefers to make contact by telephone.
In this case, 'telefonisch' is used as an adjective to describe the type of consultation, i.e., one conducted by telephone.