“Être à tu et à toi” is a French expression that translates literally to “to be at you and you”. The meaning in English is as follows:
- to be on a first name basis with somebody
- to be good friends
A French definition on expressio.fr is “to be close or informal”. In French there are two ways of saying you: tu and vous. Tu is considered informal and vous is considered formal. Hence, “être à tu et à toi” is to use the informal “tu” with somebody.
Here’s an example sentence:
- Quand j’étais a l’université j’étais à tu et toi avec mes profs: on se connaissait bien et discutait souvent après les cours. When I was in university I was on a first-name basis with my professors. We knew each other well and chatted often after class.