6,078 articles
Digit span task
The digit span task is a neuropsychological test of verbal short-term and working memory in which participants repeat heard or seen digit sequences forward, backward, or in ascending order.
Digital blackface
Digital blackface: non-Black people performing Blackness online via reaction GIFs, memes, AAVE, emojis, and video. Term coined by Joshua Lumpkin Green (2006), popularized by Lauren Michele Jackson; extends to TikTok and AI avatars.
Digital ethnography
Digital ethnography, also known as netnography, is a qualitative research method that studies culture and social interaction through participant observation and immersion in online communities, used most often in marketing and consumer research.
Dina Sanichar
Dina Sanichar was an Indian feral child found living among wolves near Bulandshahr in 1867, who spent decades in an Agra orphanage without learning to speak.
Dina Wadia
Dina Wadia (1919–2017), also called Dina Jinnah, only child of Pakistan founder Muhammad Ali Jinnah and Rattanbai Petit; married Parsi businessman Neville Wadia in 1938 against Jinnah's wishes, stayed in India, visited Pakistan twice, and fought for Jinnah House.
Dinka people
Dinka people (self-name Jieng, Muonjang): Nilotic agro-pastoral people of the upper Nile in South Sudan, largest ethnic group, cattle-centered society and religion (Nhialic), prominent in Sudanese civil wars and the Kiir-Machar rivalry.
Direct action
Direct action: confronting objectionable practices or effecting social change by readily available means such as strikes, boycotts, occupations, and civil disobedience, rather than voting; coined in 1920 labor struggles by William Mellor.
Directive counseling
Directive counseling, also called counselor-centered or prescriptive counseling, is an approach in which the counselor directs therapy, offering advice, guidance, and recommendations to the client.
Disappearance of Alex Batty
Alex Batty, an Oldham boy taken abroad in 2017 by his mother Melanie and grandfather David during a Spanish holiday, lived off-grid in a spiritual community for six years before being found near Toulouse, France in December 2023; the criminal investigation was closed in 2025.
Disappearance of Ashley Loring Heavyrunner
Ashley Loring Heavyrunner (Ashley Loring), Blackfeet woman, 20, vanished June 5, 2017, from Browning, Montana, on the Blackfeet Reservation; unsolved MMIP case, FBI and BIA investigating, no charges filed.
Disappearance of Bobby Dunbar
Disappearance of Bobby Dunbar: 1912 vanishing of a four-year-old near Opelousas, Louisiana; the boy found with William Walters was raised as Bobby, but 2004 Y-DNA proved he was Bruce Anderson, Julia Anderson's son.
Disappearance of Brandon Swanson
Disappearance of Brandon Swanson: Minnesota 19-year-old who vanished May 14, 2008, mid-call with his parents after his car went into a ditch near Taunton; searches found nothing, prompting Brandon's Law.
Disappearance of Dennis Martin
Dennis Lloyd Martin, born 1962, vanished June 14, 1969 at Spence Field, Great Smoky Mountains National Park, during a hide-and-seek game; the largest search in park history found no trace, and the case remains an open NPS cold case.
Disappearance of Don Lewis
Jack Donald "Don" Lewis, Florida millionaire and co-owner of Big Cat Rescue with wife Carole Baskin, vanished August 18, 1997, leaving only his van at a remote airport; declared dead in 2002, no arrests, case reopened in 2020 after Netflix's Tiger King.
Disappearance of Frederick Valentich
Frederick Valentich disappearance: 20-year-old Australian pilot lost over Bass Strait on 21 October 1978 flying Cessna 182L VH-DSJ to King Island after reporting a UFO; cause officially undetermined, no wreckage found.
Disappearance of Gerry Largay
Geraldine "Gerry" Largay (trail name Inchworm), a 66-year-old Appalachian Trail thru-hiker from Tennessee, vanished in Maine on July 22, 2013, survived about 26 days, and was found dead in October 2015 near a Navy SERE school.
Disappearance of Gus Lamont
August "Gus" Lamont, a 4-year-old Australian boy, vanished from Oak Park Station near Yunta, South Australia, on 27 September 2025. SAPOL's Task Force Horizon declared it a major crime in February 2026; a $1 million reward was posted in September 2026.
Disappearance of Hannah Kobayashi
Hannah Kobayashi disappearance: 30-year-old Maui photographer missing after missing a connecting flight at LAX in November 2024; found to have crossed into Mexico voluntarily at San Ysidro; father Ryan Kobayashi died by suicide during the search; she was found safe in December 2024.
Disappearance of Hannah Upp
Hannah Emily Upp, American teacher who disappeared three times (2008 New York, 2013 Maryland, 2017 St. Thomas) during dissociative fugue episodes; rescued twice, missing since September 14, 2017.
Disappearance of Jenny Pandos
Jennifer (Jenny) Pandos, born 1971, vanished February 10, 1987 from Williamsburg, Virginia at age 15, leaving a note; case file lost, parents and ex-boyfriend scrutinized, HBO's Burden of Proof covered it; unsolved.
Disappearance of Kenny Veach
Kenny Veach (Michael Veach, screenname snakebitmgee) was a Las Vegas hiker who vanished November 2014 in Nevada's Sheep Range while seeking an M-shaped cave he described in a viral YouTube comment; his phone was found near a mine shaft and he was never found.
Disappearance of Lars Mittank
Lars Mittank, German tourist from Marne, fled Varna Airport, Bulgaria on 8 July 2014 after panicking in an airport doctor's office and vanished. Also known as Lars Joachim Mittank. Distinguishing facts: ruptured eardrum, Cefprozil prescription, CCTV of his escape, unsolved.
Disappearance of Nancy Guthrie
Disappearance of Nancy Guthrie: 84-year-old Tucson woman, mother of Today co-anchor Savannah Guthrie, last seen January 31, 2026 at her Catalina Foothills home; FBI released video of a masked armed suspect, case remains unsolved.
Disappearance of Sudiksha Konanki
Disappearance of Sudiksha Konanki, 20-year-old University of Pittsburgh student who vanished March 6, 2025 at a Punta Cana beach; Joshua Riibe was detained as person of interest, later cleared; presumed drowning.
Disappearance of Tom and Eileen Lonergan
Tom and Eileen Lonergan, American divers from Baton Rouge, were left behind by the dive boat Outer Edge at St. Crispin Reef, Great Barrier Reef, on 25 January 1998; found missing two days later, never recovered; skipper acquitted of manslaughter, case inspired Open Water.
Disaster
Disaster: a serious disruption of community or societal functioning from hazardous events interacting with exposure, vulnerability and capacity (UNDRR/Sendai definition). Covers hazard-vulnerability framework, disaster studies history, mortality down 65% versus losses nearly tripled since the 1970s.
DISC assessment
DISC assessment: a self-report behavioral questionnaire based on Marston's 1928 theory, scoring Dominance, Influence, Steadiness, and Conscientiousness (or Inducement, Submission, Compliance); commercialized via Clarke's 1956 Activity Vector Analysis, Geier's Personal Profile System, and Wiley's Everything DiSC; used for workplace development, not validated for hiring.
Discipline
Discipline: training oneself or others to follow rules and regulate impulses; covers the word's Latin etymology, mental discipline in US university history, ego depletion research, and longitudinal self-control outcomes.
Discipline (BDSM)
Discipline in BDSM is the consensual system of rules, expectations, and corrective consequences within a dominance/submission dynamic, the "D" of bondage and discipline, distinguished from abuse by negotiated, withdrawable consent and safewords.
Disclosure movement
Disclosure movement: UAP/UFO disclosure advocacy network (Paradigm Research Group, Disclosure Foundation) pressing the U.S. government to release classified records; official AARO and NASA reviews find no evidence of extraterrestrial technology.