kātahi rā/hoki
1. (interjection) good grief! heavens above! goodness gracious! - an exclamation to express disapproval or amazement about an unusual idea or activity. Sometimes both rā and hoki are used for emphasis.
Kua tono a Piri mō te tūranga tumuaki o te kura. Kātahi rā hoki! Tana whakatoi hoki! / Piri has applied for the position of school principal. Goodness gracious! He's got a cheek!