on a first-name basis

Another idiom related to being on a first-name basis is "on good terms." When two individuals are on good terms, it means they have a positive and friendly relationship. They are able to communicate effectively and have mutual respect for each other. This idiom implies that there are no conflicts or disagreements between the individuals, and they are able to interact in a harmonious manner.

Furthermore, the phrase "know someone" is another idiom that can be connected to being on a first-name basis. When someone says they know someone, it means they have a familiarity with that person. It implies that they have some level of knowledge or understanding about the individual, whether it be their personality, background, or interests. This idiom suggests that there is a relationship or acquaintance between the two individuals.

Being on a first-name basis is an idiom that describes a close and familiar relationship between individuals, where they address each other by their first names. This expression conveys a sense of informality, friendship, and mutual respect. It is a phrase commonly used in American English and reflects the changing dynamics of modern relationships. Additionally, related idioms such as "on good terms," "on talking terms," and "know someone" further highlight the importance of effective communication, positive relationships, and mutual understanding in various contexts.