fraternal

Etymology

PIE word *bʰréh₂tēr Borrowed from Middle French fraternel, from Medieval Latin frāternālis (“fraternal”), from Latin frāternus (“of or pertaining to a brother, fraternal”), from frāter (“brother”).

adj

1. Of or pertaining to a brother or brothers.
   By Cognate or Domestic duties, we mean those which grow out of the different family relations; and which may be classed as conjugal, parental, filial, and fraternal. 1844, Roswell Park, Pantology; or a systematic survey of human knowledge, page 89
   The Bhratridvitiya, or fraternal rite of the Hindoos, is an institution of this nature, being admirably calculated to cement the natural bond of union between brothers and sisters of the same family. 1881, Shib Chunder Bose, The Hindoos as They Are: A Description of the Manners, Customs and the Inner Life of Hindoo Society in Bengal
   Yet, in leaving, Judah removes himself not only from fraternal violence but from familial destiny as well. 1991, From Father to Son: Kinship, Conflict, and Continuity in Genesis
2. Of or pertaining to a fraternity.
   The changing Afro-American class structure shaped the war and postwar growth of black religious and fraternal organizations in southern West Virginia. 1990, Joe William Trotter, Coal, Class, and Color: Blacks in Southern West Virginia, 1915-32
   Ambivalence toward the larger society even permeated the Reichsbanner. the only SPD fraternal organization that, on paper at least, embraced bourgeois republican groups. 1993, Donna Harsch, German Social Democracy and the Rise of Nazism
   North and South, fraternal and sororital organizations were an integral aspect of urban culture among the mass of working-class black men and women. 2005, Robin D. G. Kelley, To Make Our World Anew: A History of African Americans
   Surfer dudes and frat dudes are simply buddies; their interaction is facilitated by the homosocial context of shared sport or fraternal membership, not the willful pursuit of gay sex. 2015, Jane Ward, Not Gay, New York University Press, page 139
3. Platonic or friendly.
   He took advantage of this opportunity to consider Christian liberty in its relation to the demands of fraternal charity. 1986, Henri de Lubac, The Christian Faith: An Essay on the Structure of the Apostles' Creed
   And when he arrives he, our Sovereign, will receive you honorably because of his Tsar's Majesty's fraternal love and friendship to him. 1994, Maija Jansson, England and the North: The Russian Embassy of 1613-1614
4. (genetics) Of twins or embryos, produced from two different eggs and sperm, and genetically distinct.
   Seventy percent of twins are fraternal and result from fertilization of two separate ova by two different sperm. 2012, Leonard Crowley, An Introduction to Human Disease: Pathology and Pathophysiology Correlations, page 471
   Because each egg and each sperm of a fraternal zygote contain slightly different genetic material, these two embryos do not have identical genetic makeups. 2012, James Luce, Chasing Davis: An Atheist's Guide to Morality Using Logic and Science
   The rate of natural fraternal embryo fusion is not well documented. 2015, Sheldon Krimsky, Stem Cell Dialogues: A Philosophical and Scientific Inquiry Into Medical Frontiers, page 120

noun

1. A society formed to provide mutual aid, such as insurance.
   Here comes in the importance of the proposed bill for the uniform regulation of fraternals. 1902, “Insurance and the Fraternals”, in The Underwriters Review, volumes 11-12, page 66
   Accident and health insurance written by fraternals are discussed under the section on fraternals. 1967, Wisconsin Legislature Legislative Council, General Report of the Legislative Council to the Legislature
   The ethnic fraternals benefitted from the favorable climate for fraternalism and voluntarism that existed in the United States, and borrowed ideas and practices from native organizations such as the AOUW, and from fraternals started earlier in the century by immigrants who by now were solid members of the middle class. 2012, Ivar Berg, Sourcebook of Labor Markets: Evolving Structures and Processes
2. A fraternal twin.
   Her twins were adorable boy-girl fraternals who wore boy-girl clothes in the same fabric. 2001, Susan Kohl, Twin Stories: Their Mysterious and Unique Bond, page 14
   The bulk of the confusion concerns identicals who are really fraternals. 2005, Kevin J. Sharpe, Has Science Displaced the Soul?: Debating Love and Happiness, page 34
   Tests show that even in the first year of life, the fear of strangers develops more similarly along identical twins than fraternals. 2013, Ian Osborn, Tormenting Thoughts and Secret Rituals: The Hidden Epidemic of Obsessive-Compulsive Disorder, page 189