We found one dictionary that defines the word be on the phone:

General (1 matching dictionary)

1. be on the phone: Cambridge Advanced Learner's Dictionary

▸ Words similar to be on the phone ▸ Usage examples for be on the phone ▸ Idioms related to be on the phone ▸ Wikipedia articles (New!) ▸ Words that often appear near be on the phone ▸ Rhymes of be on the phone ▸ Invented words related to be on the phone