ORDER By N., Sam M.S. - 20 noun. With regard to biological taxonomy, a primary subset of a category, consisting of a set of like, corresponding families. ORDER: "The order is expressed with numbers, and the classes by letters, in the textbook." Related Psychology Terms FAMILY CARE ADOLESCENCE (Theories) SOCIAL CLASS (Social Stratification) READINESS TESTS Piaget’s Theory of Cognitive Development A Comparison of Maternal and Paternal Filicide MENTAL RETARDATION (PREVENTION, CARE, AND TREATMENT) COLOR BLINDNESS Selecting a Diagnosis PHYLUM Cite this page: N., Sam M.S., "ORDER," in PsychologyDictionary.org, April 7, 2013, https://psychologydictionary.org/order/ (accessed September 24, 2022).