The main collective noun for Deer is a herd. Other collective nouns for a Deer include a bevy, a brace, a bunch, a gang, a leash, a mob, a parcel, and a rangale. The term herd is derived from the Old English word “heord”, which was used to describe a group of animals. This term was used to refer to a group of Deer, as well as other animals such as sheep and cattle. The term herd is used to describe a group of Deer because it implies that the animals are travelling together in a large group, which is a common behavior of Deer.