Chork's Puzzle 23

Difficulty Rating: 3

Below are 7 clues to 7 different words, which have a similar property.

Clues:
1. Furtive glance
2. High frequency radio wave
3. Adam
4. Single performances
5. Vision
6. Sister
7. Doctrine

After you solved the 7 words, the first letters of each of these words (in the given order), spells a new word!

What is the 7 letter word?
If you know the answer, post it in the comments section of this post.