Seventh-Day Adventists are generally Vegetarians
religious pacifist
peak associations
blanket customer groups
A pressure group is an organization whose members seek to influence the policies of public bodies or employers.
Rock The only '60's band with all members still alive are The Kinks...
Jehovahs Witnesses, Amish, and apparently quakers
That is relating to religious orders whose members are forbidden to own property and must work or beg for their living
Reading between the lines a bit... You may be thinking of certain religious sects whose members often wear clothing that most Americans would consider "old-fashioned." The two most prominent of these groups are the Amish and the Mennonites.
James Jones led a religious cult whose members committed mass suicide in Gayana, Africa in the 1970's.
It is not a common expression, but it is sometimes used in organizational behavior (business), sociology or psychology. It refers to the difference between two types of groups: "fixed groups" are those whose members stay together for a long time; "revolving groups" are those with members that only stay together until a specific task is accomplished.
Primary group is a small social group whose members share personal and enduring relationship. Secondary group is a large social group and impersonal group whose members pursue a specific goal or activity.
It depends on what size "group" one is talking about. There were two big groups, the Ornithischians, whose members had hips like those of modern birds, and the Saurischians, whose hips were more lived those of lizards. Within these two groups, there were smaller, but still pretty populous, groups of Theropods, Sauromorphopods, Stegosaurs, Ankylosaurs, Ceratopsians, Hadrosaurs, Pachycephosaurs, Dromaeosaurs, Ornithomimi, and probably others that haven't been discovered. The smaller groups are the Genera, and these are the names you know: Apatosaurus, Tyrannosaurus, Triceratops, etc.