According to the Oxford English Dictionaries, the standard collective noun used to refer to a group of domestic cats is a 'clowder,' as in 'a clowder of house cats.' Other sources indicate that there may be other collective nouns that can be applied to cats, though these may be more colloquial in nature. Alternate collective nouns for a group of domestic cats include clutter, pounce, glare, nuisance, cluster and glaring.
There are also collective nouns to describe groups of other types of cats. For example, a group of kittens is usually referred to as a litter, but this adorable grouping can also be referred to as a kindle or an intrigue of kittens, as in, 'There is a kindle of kittens available for adoption at the library today.' Wild cats also have their own collective nouns. A herd of lions is typically referred to as a pride, but can alternately be called a troop or a sawt. A grouping of tigers can be known as a streak or an ambush, while a group of leopards can be called a leap or lepe. Collective nouns for wild cats in general include 'destruction,' as in, 'The school children saw a destruction of different big cats at the zoo today.'