All articles starting with R
22,461 articles
Red-bellied black snake
The red-bellied black snake (Pseudechis porphyriacus) is a venomous elapid snake of eastern Australia, glossy black above with red to pink lower sides, usually found near streams and swamps.
Red-bellied piranha
Red-bellied piranha (Pygocentrus nattereri, syn. Serrasalmus nattereri), a schooling South American serrasalmid fish of the Amazon, Paraguay-Parana, and Essequibo basins; omnivorous predator and scavenger up to 50 cm, known for powerful interlocking teeth and single-bite brood-defense injuries to bathers.
Red-bellied woodpecker
Red-bellied woodpecker (Melanerpes carolinus), an eastern and central US woodpecker with a barred back, red crown and nape, and a rarely seen red belly. Cavity nester, omnivorous, resident year round, population about 16 million and increasing.
Red-crowned crane
The red-crowned crane (Grus japonensis), also called the Japanese crane or tancho, is a vulnerable crane of East Asia known for the red patch on its crown.
Red-eared slider
Red-eared slider (Trachemys scripta elegans), a semiaquatic pet-trade turtle with a red eye stripe, native to the south-central US and northeastern Mexico, listed among IUCN's 100 worst invasive species with feral populations worldwide.
Red-eye effect
The red-eye effect is a photographic artifact where flash light entering dilated pupils reflects off blood vessels at the back of the eye, making pupils appear red in photos.
Red-eye flight
A red-eye flight is an overnight airline flight departing late at night and arriving early the next morning, named for the tired eyes of sleepless passengers.
Red-eye gravy
Red-eye gravy, or redeye gravy, is a thin Southern US breakfast sauce of country ham pan drippings deglazed with strong black coffee; it has no thickener, separates into a red-eyed appearance in the bowl, and contrasts with thick, flour-thickened sawmill gravy.
Red-figure pottery
Red-figure pottery: Greek vase-painting technique, invented in Athens around 530 BCE, with red figures reserved on a black gloss ground, brush-drawn details, three-stage firing, spread to South Italy and Etruria, extinct by the third century BCE.
RED-FLAG 2 study
RED-FLAG 2 (NCT05820217) is a French prospective observational study led by University Hospital, Angers, externally validating the pre-hospital Red Flag alert for severe haemorrhage in blunt trauma across six SAMU centers, 630 participants.
Red-headed woodpecker
Red-headed woodpecker (Melanerpes erythrocephalus), a crimson-headed North American cavity-nesting woodpecker that flycatches and caches food under bark; Near Threatened (IUCN), Endangered in Canada (COSEWIC 2018), with a 54% decline from 1966 to 2019.
Red-light district
Red-light district: an urban area where prostitution and sex-related businesses are concentrated and visible, formal tolerance zones or informal clusters; examples include Amsterdam's De Wallen, Soho, and Leeds' managed zone.
Red-light running
Red-light running is the act of a driver entering an intersection after the traffic signal has turned red; drivers already in the intersection when the signal changes are not violators.
Red-rimmed melania
Red-rimmed melania (Melanoides tuberculata), also Malaysian trumpet snail, a thiarid freshwater snail native to Africa and southern Asia, parthenogenetic, aquarium-traded, and invasive worldwide, transmitting trematode parasites.
Red-shanked douc
Red-shanked douc (Pygathrix nemaeus), Critically Endangered colobine monkey of Laos, Vietnam, and Cambodia; foregut-fermenting folivore; largest population in Nakai–Nam Theun, Laos.
Red-shouldered hawk
Red-shouldered hawk (Buteo lineatus), also Busardo Pechirrojo or Buse à épaulettes: a medium-sized North American forest buteo of wet woods, with barred reddish underparts, banded tail, kee-rah call, five subspecies, and Low Concern status.
Red-tailed hawk
Red-tailed hawk (Buteo jamaicensis), the most common North American Buteo hawk, named for the adult's cinnamon-red tail. Large open-country raptor, 690–1,460 g, mammal-heavy diet, 3.1 million breeding birds, low conservation concern.
Red-teaming (foundation models)
Red-teaming of foundation models is the structured adversarial testing of AI systems to find harmful capabilities, outputs, or vulnerabilities, formalized by OpenAI, government mandates, and benchmarks like HarmBench.
Red-teaming of image and video generation models
Red-teaming of image and video generation models systematically searches for prompts that bypass safety filters in diffusion-based text-to-image and text-to-video systems, a distinct safety subfield since 2023.
Red-winged blackbird
Red-winged blackbird (Agelaius phoeniceus), Sargento Alirrojo, Carouge à épaulettes: abundant North American icterid of marshes; glossy black male with red-and-yellow epaulets, polygynous harems up to 15 females, 180 million population declining 28% since 1966.
Red–black tree
A red–black tree, or symmetric binary B-tree, is a self-balancing binary search tree invented by Rudolf Bayer in 1972 and used in Java's TreeMap, C++ std::map, and the Linux kernel.
Red–Green Alliance (Denmark)
The Red-Green Alliance (Enhedslisten, De Rød-Grønne) is Denmark's far-left socialist party, founded in 1989 by three Marxist parties and in the Folketing since 1994. It holds ballot letter Ø, has no chairman, uses rotation and gender quotas, and peaked at 7.8% in 2015.
Red, Hot and Blue (film)
Red, Hot and Blue (1949) is a Paramount musical comedy directed by John Farrow, starring Betty Hutton and Victor Mature, with four Frank Loesser songs and Loesser's only film acting role; unrelated to the 1936 Cole Porter musical of the same name.
Red, White & Royal Blue
Red, White & Royal Blue: 2019 queer romance debut novel by Casey McQuiston (St. Martin's Griffin) in which First Son Alex Claremont-Diaz falls for Prince Henry of Wales; NYT bestseller, 2023 Prime Video film, sequel and novella announced.
Red, White & Royal Blue (film)
Red, White & Royal Blue is a 2023 Prime Video romantic comedy directed by Matthew López, adapted from Casey McQuiston's 2019 novel, starring Taylor Zakhar Perez and Nicholas Galitzine; its sequel Red, White & Royal Wedding is in post-production.
Red, White & Royal Wedding
Red, White & Royal Wedding is the Prime Video sequel to Red, White & Royal Blue (2023), directed by Jamie Babbit, starring Nicholas Galitzine and Taylor Zakhar Perez; filmed January to March 2026, now in post-production, wedding belongs to Princess Beatrice.
Reda Elazouar
Reda Elazouar (also Reda El Azouar), British actor born in London in 1999 to a Moroccan family; breakout as Kidda in Pirates (2021), Beau in Sex Education season 4, Omar in The Family Plan 2, and Karim Lapointe in Maigret.
Redacted
Redacted (2007) is Brian De Palma's Iraq War drama, a fictional documentary-style collage based on the 2006 Mahmudiyah rape and murder, released by Magnolia Pictures.
Redaction
Redaction is the removal or blocking out of sensitive, identifying, or otherwise non-disclosable information from documents and datasets before they are released, especially in government contexts.
Redaptive
Redaptive is an American energy technology company, founded in 2015 and based in Denver, Colorado, that funds, installs, and owns efficiency equipment such as LED lighting, HVAC, and solar.