Scruple - A very small amount, or part of something or something which is small in itself or a hesitancy which prohibits you from choosing the right thing or judging something.
Open Word Class - Noun
1. A scruple ant can also kill a lion.
2. Well, the money which I have currently with me is the reason for the scruple that I am not able to buy the correct thing.
3. This world is so big a scruple that you never know what you actually are going to face next.