Trepidation

/ˌtrɛpɪˈdeɪʃən/ noun medium

A feeling of fear or nervous uncertainty about something about to happen.

She walked into the interview room with more trepidation than she wanted to admit.

Memory Trick

Trepidation comes from Latin 'trepidare,' to tremble -- it is that trembling feeling in your stomach right before something uncertain begins.