IPA: /tɛləˈfɒnɪkli/
KK: /tɛlɪˈfoʊnɪkli/
In a way that involves using a telephone to communicate.
She contacted her friend telephonically to discuss the plans for the weekend.
Telephonically → It is formed from "tele-" (from Greek "tēle", meaning far off or at a distance) and "phone" (from Greek "phōnē", meaning voice or sound) and the suffix "-ically" (meaning in a manner relating to). The word "telephonically" means in a manner relating to communication over a distance by voice.
Think of 'far off' ('tele-') and 'voice' ('phone') to remember that 'telephonically' refers to communicating by voice over a distance.