effrontery (noun)

1. The serial killer had the effrontery to taunt the police by sending them a letter describing his next victim.

2. She walked into the fancy restaurant with such effrontery, wearing a bright pink feathered hat and a sequined gown.

3. The villain in the cartoon had the effrontery to steal all the cakes from the bakery and laughed as the townspeople chased after him.

4. With effrontery, he dropped down to one knee and declared his love for her in front of the entire restaurant.