Tutoie

I took a particular delight in talking to her in French when she was angry, especially in tutoieing her, it made her so “wrathy.”

Source: wiktionary

A French teacher, by the use of ‘thou’ instead of ‘you,’ informs his pupil that he regards him as a friend; and he at once reciprocates the feeling by tutoieing in return.

Source: wiktionary

One further short cut, a line or two of dialogue between the Prince and Migaev in the second act, has been made because they discuss the pros and cons of tutoieing, which is meaningless in English.

Source: wiktionary

LS tutoies men (Rich, AO), whom he treats as buddies, and vousvoies women (Sally, La Directrice), adopting with them the role of chivalrous patron;

Source: wiktionary