Myeh

An expression or noise made when mimicking someone who is moaning or telling you off.

Chrissie: *gives lecture on how busy she is*
Sarah: 'Myeh myeh myeh'
Chrissie: STOP IT
Sarah: 'MYEH'
Chrissie: Sarah...
Sarah: Myeh?
Chrissie: Stop
Sarah: Myehokay...