a word or expression used to show many emotions- embarrassment, shock, disgust, or just used in any point in a conversation. It has many, many variations and the simplest 'ehh' base serves as a model for other variations. As long as it has the distinct 'ehh' sound, one can improvise. Use with intonation.
P1:"I heard they were going out... gross right?"
P1: "The test is today! Oh my God!"
P2: Ehhh! I didn't study!