A sharp burst of cold air or icy temperatures is a chill. The chill of a January day in New England might make you dream of moving to New Mexico.
You'll feel a chill when someone opens a window in the winter, or notice a chill in the air on a cool day in September. Another kind of chill makes you shiver, but it's caused by illness and fever rather than a cold breeze: "Symptoms of the flu include chills and headache." A cold attitude is also a chill, as when a chill in the room makes you realize your friends are angry at each other.