A ‘collective noun’ is a noun used to refer to a group of things as a whole–simple ones include a “group”, a “flock”, or a “pack”. The English language especially, however, has a tradition of whimsical, comical, or absurd names for specific groups of things.
On October 19, 1762 the day was so dark at Fort Detroit that candles were needed to see at noon. A British officer called the day "The most extraordinary dark day perhaps ever seen in the world." Some would take the darkness as a sign.
Solenopsis invicta, the “Red Imported Fire Ant”, native to South America, has proven a tenacious and destructive pest in the United States, costing Americans billions of dollars every year. That is why, in the late 1950s, the United States embarked on an all out war against the six-legged menace.