gee whiz
1. modifier (hyphenated and used before a noun) Especially enthusiastic or impressed; youthfully or na?vely optimistic or exuberant. The film is sure to provoke some gee-whiz reactions from even the most cynical of spectators. A lot of people come into politics with some gee-whiz notions of changing the world.
2. modifier (hyphenated and used before a noun) Showily or gaudily impressive; amazing or astounding. The film boasts a lot of gee-whiz effects but doesn't offer much else in the way of plot or character development.
3. interjection An exclamation of any strong emotion, such as surprise, dismay, enthusiasm, exasperation, etc. Aw, gee whiz, Mom! Can't I stay out and play for one more hour? Gee whiz guys, wasn't that show great?
gee whiz
An expression of surprise, dismay, or enthusiasm. For example, Gee whiz, Dad, I thought you'd let me borrow the car, or Gee whiz, they finally won the Series! This term is thought to be a euphemism for "Jesus Christ." [Slang; 1870s]