2,229 articles
Immediate family
Immediate family: the closest circle of relatives, usually spouse, parents, and children. No single legal definition exists; US labor, criminal, immigration, state, Canadian, and Australian rules each define it differently.
Immigration effects of same-sex relationships
The immigration effects of same-sex relationships cover how binational LGBT couples obtain residency through partner sponsorship or asylum, a US pathway barred by DOMA until the Supreme Court struck it down in 2013.
Impact play
Impact play is a consensual BDSM activity of striking a partner with hands or implements (paddles, floggers, canes) for sensation and power exchange; risks concentrate on head, neck, kidneys, and genitals.
Incel
Incel (involuntary celibate) is an online subculture of men who define themselves by perceived inability to form romantic relationships; coined by a woman in the 1990s, now part of the manosphere, marked by blackpill ideology, rare but high-profile violence, and widespread mental health struggles.
Incest
Incest is sexual activity or marriage between close relatives within prohibited degrees of consanguinity. Covers the near-universal incest taboo, Westermarck and inbreeding explanations, genetic risks, comparative criminal law, and family-member sexual abuse statistics.
Incest between twins
Incest between twins: sexual activity or marriage between co-twin siblings, treated under general sibling incest law. Covers Balinese and Zulu twin beliefs, the Westermarck effect, the 2008 co-twin marriage case, genetic risks, and legal status.
Incest in the Bible
Incest in the Bible covers the prohibited-relationship lists of Leviticus 18 and 20 and Deuteronomy 27, narratives of Lot's daughters, Judah and Tamar, and Amnon and Tamar, ancient Near Eastern parallels, and the Qur'anic reception in Q 4:22–23.
Incest taboo
Incest taboo is a cultural rule prohibiting sexual relations or marriage between close relatives. It exists in every human society, though its scope varies widely.
Incidents of necrophilia
Incidents of necrophilia, also called sexual attraction to corpses, a rare paraphilia; documented through Rosman and Resnick's 122-case review, Aggrawal's 10-class system, and homicidal case studies.
Independent Living
Independent living: disability-rights philosophy and movement, founded in Berkeley in 1972 by Ed Roberts and others, holding that people with disabilities control their own lives; implemented through over 350 U.S. centers for independent living under Rehabilitation Act Title VII.
Industrial and Commercial Workers' Union (South Africa)
The Industrial and Commercial Workers' Union (ICU) was a general trade union for black, Coloured, and Indian workers in South Africa, founded in Cape Town in 1919.
Industrial Society and Its Future
Industrial Society and Its Future, the 35,000-word Unabomber manifesto by Theodore Kaczynski (FC), published by the Washington Post in 1995, arguing industrial society cannot be reformed and must be destroyed.
Infidelity
Infidelity is secret emotional, sexual, or romantic behavior that breaks a relationship's agreed exclusivity; the sexual form in marriage is adultery, a leading cause of divorce and separation.
Innuendo
Innuendo, from Latin innuendo "giving a nod to," is an indirect, deniable hint, often sexual, or disparaging; also a legal pleading term and the psychological "innuendo effect" of negative inference from omission.
Institut für Sexualwissenschaft
Institut für Sexualwissenschaft, Magnus Hirschfeld's 1919 Berlin institute, the world's first sexology research and clinic center; performed early gender-affirming surgeries, destroyed by Nazi students in May 1933.
Institutional racism
Institutional racism: racial discrimination embedded in institutional policies, practices, and procedures; coined by Carmichael and Hamilton in Black Power (1967); distinct from structural racism, which operates across institutions.
Intercrural sex
Intercrural sex, also called interfemoral sex or thigh riding, is non-penetrative sex between the thighs. Article covers its definition, Kenneth Dover's ancient Greek scholarship and the revisionist critique, and survey prevalence data.
Interfaith marriage
Interfaith marriage, also called religious intermarriage or mixed marriage, is marriage between partners of different religions; about 26% of U.S. marriages are interfaith, with Islamic and Catholic canon rules and legal restrictions in some countries.
Interfaith marriage in Christianity
Interfaith marriage in Christianity: marriage between Christians of different traditions or between a Christian and a non-Christian; governed by Catholic canon law (mixed marriage, disparity of cult), Orthodox Trullo canon 72, and rising U.S. intermarriage rates.
Interfaith marriage in Islam
Interfaith marriage in Islam covers marriages between Muslims and non-Muslims, governed by Quran 2:221, 5:5, and 60:10. Sunni law permits men to marry Jewish or Christian women but bars the reverse for women; Shia law is stricter, and Indonesia, Malaysia, and Brunei codify the rules differently.
Interfaith marriage in Judaism
Interfaith marriage in Judaism is marriage between a Jew and a non-Jew, forbidden under halakha but common among non-Orthodox American Jews. Key facts: 61% of recent U.S. Jewish marriages are interfaith, 2% among the Orthodox; Reform rabbis may officiate, Conservative rabbis are barred.
Internal resistance to apartheid
Internal resistance to apartheid: South African opposition inside the country, from the 1960 banning of the ANC and PAC, through Black Consciousness (SASO 1969), the 1976 Soweto Uprising, black trade unions, and the UDF (1983), to the states of emergency of 1985-1986.
International adoption of South Korean children
International adoption of South Korean children: roughly 200,000 children sent abroad since 1953, the world's largest intercountry adoptee diaspora. Also known as Korean overseas adoption or 해외입양. Marked by the 1961 orphan law, falsified records, a 2025 truth commission finding of state responsibility, and Hague Convention ratification effective October 1, 2025.
International Day of the Girl Child
International Day of the Girl Child is a UN observance on 11 October, created by Resolution 66/170 in 2011 and first held in 2012. Annual themes address girls' rights; the 2026 theme targets child marriage, which affects over 12 million girls yearly.
International Day of Yoga
International Day of Yoga, a UN observance on 21 June since 2015, established by resolution 69/131 after Narendra Modi's 2014 UNGA proposal; annual themes include Yoga for Healthy Ageing (2026).
International Dog Day
International Dog Day, also called National Dog Day or Dog Appreciation Day, is an August 26 observance founded in 2004 by Colleen Paige, marking the date her family adopted a Sheltie, that celebrates dogs and encourages shelter adoption, distinct from World Dog Day (May, Vanderpump Dog Foundation) and National Rescue Dog Day (May 20).
International Fellowship of Christians and Jews
The International Fellowship of Christians and Jews (IFCJ) is a Chicago-based nonprofit founded in 1983 by Rabbi Yechiel Eckstein that raises Christian donations for Jewish humanitarian aid.
International Lesbian, Gay, Bisexual, Trans and Intersex Association
ILGA World (International Lesbian, Gay, Bisexual, Trans and Intersex Association), founded 1978 in Coventry, is a federation of 2,000+ LGBTI organisations in 170+ countries with UN ECOSOC status; its ILGA-Europe branch publishes the Rainbow Map.
International Men's Day
International Men's Day, observed 19 November worldwide, founded 1999 by Jerome Teelucksingh in Trinidad and Tobago after Thomas Oaster's 1992 February version; Six Pillars, around 80 countries, not a UN observance.
International Transgender Day of Visibility
International Transgender Day of Visibility (TDOV), held annually on March 31, was founded in 2009 by Rachel Crandall-Crocker of Transgender Michigan as a worldwide celebration of living transgender people, contrasting with the November 20 Transgender Day of Remembrance.