あいづち responding during conversation

言葉の語源 kotoba no gogen - The origin of words:

あいづち aizuchi [相槌]

Meaning: verbal or non verbal responses of agreement while someone is speaking. (While listening to someone you nod for example)

Hint: Remember the "zu" is づ

Example: あの人のはなしは面白くなかったけれど、一応あいづちを打ちながら聞いていた。

ano hito no hanashi wa omoshiroku nakatta keredo, ichiou aizuchi o uchina