タメ語
also: ためご
タ
メ
ご
Meanings
1
casual language; informal speech
Refers to the casual, non-polite speech style used between close friends or people of equal status. Often contrasted with 敬語 (keigo, polite language) or 丁寧語 (teineigo, polite language).
It's rude to use casual language with a senior.
Since we're close, I always speak to him in casual language.