English-speakers classify up to four distinct groups of relatives as cousins. The children of a set of brothers and sisters form the primary category: they are first cousins to each other. More distantly related kin of one's own generation (collateral kin) form the second category. The grandchildren of your grandparents' siblings are your second cousins; the great-grandchildren of your great-grandparents' siblings are your third cousins; and so forth. (To put this in another way, children of first cousins stand as second cousins to each other while grandchildren stand as third cousins). The third and potentially broadest category includes the children of aunts, uncles, and cousins who belong to a different generation from one's self. The child of your second cousin, for instance, is technically your second cousin-once-removed, as you are to her (the terms are reciprocal). Finally, some English-speakers refer to the cousins of spouses and other in-laws as cousin, although these people are not technically kin. It is important to note that people do not use these categories consistently, especially with more distant kin.
The categorical expansiveness of cousin in English and other European languages rests on a distinction between the nuclear family and more distant kin. This kind of kinship terminology system is technically known as Eskimo and is also found in small hunter-gatherer groups that lack strong descent groups. Other societies classify kin differently. Hawaiian terminology, found in Polynesia and many West African cultures, provides the simplest variation. All relatives are classified according to generation. There is no distinct term for cousin in the English sense. Collateral relatives are referred to by the same terms as brother and sister (Keesing 1975).
Most societies with unilineal descent systems make a finer distinction between cross and parallel relatives. Parallel cousins include the children of one's father's brothers and mother's sisters. In general, one refers to parallel cousins by the same terms as one's own siblings and to their parents as father and mother. Cross-cousins include the children of one's father's sisters and mother's brothers. They receive a special term, as do their parents and children, indicating their separation from the immediate family. A range of societies in the Americas, Oceania, and southern Asia prefer marriage between cross-cousins. This kind of marriage forms strong and lasting alliances between the groups exchanging spouses, even when, as is often the case, the marriage is between classificatory cross-cousins—that is, people who share at best a distant genealogical relationship but who refer to each other as cross-cousins (Lévi-Straus 1969). A few Middle Eastern societies prefer marriages between parallel cousins, a pattern that enforces marriage within a descent group (Holy 1996).
Cousins often enjoy warm relationships, even in societies with weak extended family systems. Societies differ in the degree to which closely related cousins are regarded as immediate family and thus subject to the incest taboo. The U.S. rock-and-roll star Jerry Lee Lewis was widely condemned in 1958 for marrying a second cousin (and criticized also because she was only thirteen at the time). On the other hand, such respected figures as Charles Darwin and Queen Victoria married first cousins. Most U.S. states ban or place severe restrictions on first cousin marriages, but such marriages are legal in Canada and Europe (Ottenheimer 1996).
Holy, L. (1996). Anthropological Perspectives on Kinship. London: Pluto Press.
Keesing, R. M. (1975). Kin Groups and Social Structure. New York: Holt, Rinehart, and Winston.
Lévi-Straus, C. (1969). The Elementary Structures of Kinship. London: Eyre and Spottiswood.
Ottenheimer, M. (1996). Forbidden Relatives: The American Myth of Cousin Marriage. Urbana: University of Illinois Press.