—n. 1. parents and their children, considered as a group, whether dwelling together or not.
2. the children of one person or one couple collectively: We want a large family. 3. the spouse and children of one person: We're taking the family on vacation next week. 4. any group of persons closely related by blood, as parents, children, uncles, aunts, and cousins: to marry into a socially prominent family. 5. all those persons considered as descendants of a common progenitor.
6. Chiefly Brit.approved lineage, esp. noble, titled, famous, or wealthy ancestry: young men of family. 7. a group of persons who form a household under one head, including parents, children, and servants.
8. the staff, or body of assistants, of an official: the office family. 9. a group of related things or people: the family of romantic poets; the halogen family of elements. 10. a group of people who are generally not blood relations but who share common attitudes, interests, or goals and, frequently, live together: Many hippie communes of the sixties regarded themselves as families. 11. a group of products or product models made by the same manufacturer or producer.
12. Biol.the usual major subdivision of an order or suborder in the classification of plants, animals, fungi, etc., usually consisting of several genera.
13. Slang.a unit of the Mafia or Cosa Nostra operating in one area under a local leader.
14. Ling.the largest category into which languages related by common origin can be classified with certainty: Indo-European, Sino-Tibetan, and Austronesian are the most widely spoken families of languages. Cf. stock (def. 12), subfamily (def. 2).
15. Math. a. a given class of solutions of the same basic equation, differing from one another only by the different values assigned to the constants in the equation.
b. a class of functions or the like defined by an expression containing a parameter.
c. a set.
—adj. 1. of, pertaining to, or characteristic of a family: a family trait. 2. belonging to or used by a family: a family automobile; a family room. 3. a. suitable or appropriate for adults and children: a family amusement park. b. not containing obscene language: a family newspaper. 4. in a or the family way, pregnant.