All articles starting with R
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Rooster Teeth
Rooster Teeth was an Austin, Texas-based digital media company founded in 2003, known for Red vs. Blue and RWBY, shut down by Warner Bros. Discovery in 2024.
Root
Root (botany): the plant organ that anchors the plant and absorbs water and minerals. Also called taproot or fibrous root systems; evolved independently in at least two vascular plant lineages in the Early Devonian, c. 410-395 million years ago.
Root anomaly
Root anomaly (ICD-11 DA07.4, 歯根異常): a developmental dental disorder altering tooth root number, shape, or size, including short root anomaly, dilaceration, and taurodontism, often linked to HERS disruption, trauma, or genetic syndromes.
Root beer
Root beer is a sweetened American carbonated soft drink flavored primarily with sassafras, plus sarsaparilla, vanilla, and wintergreen; commercial versions use artificial or safrole-free flavoring since the FDA's 1960 safrole ban.
Root canal
Root canal treatment (endodontic therapy) removes infected dental pulp, disinfects and seals the root canals to save a tooth. Pooled survival is 86-93% over 2-10 years; outcomes rival dental implants at lower cost.
Root canal treatment
Root canal treatment (endodontic therapy) removes infected tooth pulp, cleans and seals the canal with gutta-percha; success 85–93%, survival above 95%, comparable to dental implants at lower cost.
Root cap
Root cap (calyptra): protective tissue covering the root tip of most vascular plants, sensing gravity, water, salt, and microbes via columella statocytes, shedding border cells and mucilage, and turning over through FEZ/SMB-regulated cell death.
Root cause analysis
Root cause analysis (RCA) is a structured method for finding the root causes of an undesired outcome, used in aviation, healthcare, manufacturing, and software engineering.
Root cellar
A root cellar is an underground or insulated room that uses the ground's cool, stable temperature and humidity to store vegetables and fruits without electricity.
Root certificate
A root certificate, also known as a Root CA, is a self-signed X.509 certificate that serves as the starting point of a chain of trust for verifying other certificates.
Root culture
Root culture is a plant tissue culture technique in which isolated roots are grown aseptically in nutrient medium, pioneered by Philip R. White with tomato roots in 1934.
Root directory
The root directory (root folder) is the topmost directory of a file system. In Unix it is written as a single slash (/), from which all absolute paths start.
Root fracture
Root fracture (ICD-11 NA0D.06), a dental injury involving dentin, cementum, and pulp; treated by repositioning and flexible splinting, with survival depending on fracture location and healing type; distinct from vertical root fractures.
Root inoculation
Root inoculation is the application of beneficial microorganisms, most commonly rhizobia, to legume seed or soil so young roots form symbioses that improve nutrient uptake, growth, and yield.
Root locus
The root locus is a control engineering method that plots a closed-loop system's poles in the complex plane as feedback gain varies, used to judge stability.
Root mean square
The root mean square (RMS), also called the quadratic mean, is the square root of the mean of the squares of a set of values, used for varying quantities like AC voltage.
Root name server
A root name server, or DNS root server, is an authoritative name server for the DNS root zone, with 13 identifiers served from more than 1,500 anycast instances worldwide.
Root nodule
Root nodule: legume root organ housing nitrogen-fixing rhizobia (Rhizobium, Bradyrhizobium, Sinorhizobium). Discovered by Hellriegel and Wilfarth in 1880; leghemoglobin keeps oxygen at 3–22 nM for nitrogenase.
Root of unity
A root of unity is a complex number whose some power equals 1; the n-th roots of unity form the vertices of a regular n-gon on the unit circle.
Root planing
Root planing, known with scaling as scaling and root planing (SRP), is a dental procedure that removes plaque and calculus from tooth roots below the gumline to treat periodontitis.
Root polytope
A root polytope is the convex hull of the roots of a root system, centrally symmetric and containing the origin, studied in Lie theory and lattice-point counting.
Root pruning
Root pruning is the deliberate cutting or restriction of plant roots to slow shoot growth, build a fibrous root system, or shift a tree's balance toward fruit.
Root race
In Theosophy, a root race, or culture epoch, is one of seven evolutionary stages of humanity taught by Helena Blavatsky in The Secret Doctrine, including the Lemurian and Atlantean races.
Root resection
Root resection is a dental procedure that removes one root of a multi-rooted tooth while leaving the crown intact, to save a molar with healthy remaining roots.
Root server system governance agreements
Root server system governance agreements are the contracts and memoranda coordinating the DNS root zone, ranging from the binding 2016 ICANN–Verisign agreement to mostly voluntary arrangements with root server operators.
Root Sports Northwest
Root Sports Northwest was a Bellevue, Washington-based regional sports network (launched 1988 as Northwest Cable Sports; also Prime Sports, FSN Northwest) that aired Seattle Mariners games, was majority then fully owned by the Mariners, and shut down December 31, 2025, with MLB taking over Mariners broadcasts in 2026.
Root system
A root system is a finite set of vectors in a Euclidean space closed under perpendicular reflections, encoding the symmetry of semisimple Lie algebras and classified by Dynkin diagrams.
Root test
The root test, also called Cauchy's root test or the nth-root test, decides whether an infinite series converges by examining the nth roots of its terms.
Root vegetable
Root vegetable: culinary category of edible underground storage organs, including taproots (carrot, beet), tuberous roots (sweet potato), stem tubers (potato), corms, rhizomes, and bulbs; starchy staple crops central to food security.
Root-knot nematode
Root-knot nematodes (Meloidogyne spp.) are microscopic soil roundworms that invade plant roots and form galls; about 100 species, ranked first among plant-parasitic nematodes, infecting over 3000 plant species including tomato, cotton, and rice.