All articles starting with S

Sagitta

Sagitta, the Arrow, is a small northern constellation between Cygnus and Aquila, one of the oldest named patterns in the sky and third-smallest of the 88.

Sagittal abdominal diameter (SAD, abdominal height) is the supine front-to-back abdominal thickness measured by caliper at the iliac crests; it estimates visceral fat and predicts dysglycemia and coronary heart disease beyond BMI and waist circumference.

Sagittal plane

Sagittal plane: vertical antero-posterior anatomical plane dividing the body into right and left parts; median (midsagittal) plane bisects it equally, parasagittal planes unequally; flexion and extension occur in it.

Sep 29, 2026

Sagittal split ramus osteotomy

The sagittal split ramus osteotomy (SSRO), usually done bilaterally as BSSO, is jaw surgery that splits the mandibular ramus to advance, set back, or rotate the lower jaw.

Sagittaria

Sagittaria (arrowhead, duck potato) is a cosmopolitan genus of aquatic Alismataceae herbs published by Linnaeus in 1753, type S. sagittifolia, with sagittate leaves, unisexual whorled white flowers, edible tubers, and a South American origin.

Sagittarius (constellation)

Sagittarius, the Archer, is a zodiacal constellation of the southern sky lying toward the Milky Way's center, which it contains along with the black hole Sagittarius A.

Sagittarius A

Sagittarius A is a complex of radio sources at the center of the Milky Way, including Sagittarius A, the supermassive black hole about 4 million times the Sun's mass.

Sagittarius A West

Sagittarius A West is the thermal H II region at the center of the Milky Way, a spiral-shaped cloud of ionized gas known as the minispiral.

Sagittarius A*

Sagittarius A (Sgr A, Sagittarius A-star) is the supermassive black hole at the center of the Milky Way, about 4 million solar masses and 26,000 light-years from Earth.

Sagittarius Arm

The Sagittarius Arm, also called the Sagittarius-Carina Arm, is a spiral arm of the Milky Way, lying inward of the Sun and traced by young stars and star-forming regions.

Sagittarius B2

Sagittarius B2 (Sgr B2) is a giant molecular cloud near the Milky Way's center that holds 10 percent of the region's gas yet forms about half its stars.

Sagittarius C

Sagittarius C is a star-forming molecular cloud about 200 light-years from the Milky Way's central black hole, known for its unusually low star formation rate.

Sagittarius Dwarf Spheroidal Galaxy

The Sagittarius Dwarf Spheroidal Galaxy (Sag DEG) is the closest known satellite galaxy of the Milky Way, discovered in 1994 and currently being tidally torn apart by its larger host.

Sagittarius Stream

The Sagittarius Stream is a ribbon of stars stripped from the Sagittarius dwarf spheroidal galaxy by the Milky Way, encircling the Galaxy in a nearly polar orbit.

Sagliker syndrome

Sagliker syndrome, also called uglifying human face syndrome, is a rare severe renal osteodystrophy from untreated secondary hyperparathyroidism in chronic kidney disease, causing facial and skeletal deformity, hearing loss, and neuropsychiatric symptoms; first described 2004.

Sagnac effect

The Sagnac effect is the phase shift between two waves sent in opposite directions around a rotating closed path, first demonstrated by Georges Sagnac in 1913.

Sagnac interferometer

The Sagnac interferometer is an optical interferometer whose counter-propagating beams shift in phase when the loop rotates, an effect Georges Sagnac first measured in 1913.

Sago

Sago (Metroxylon sagu, rumbia): starch from the trunk of a swamp-adapted Southeast Asian palm, a staple food in eastern Indonesia and Papua; yields up to 25 t/ha, harvested after 8-12 years, with food and industrial uses.

Sago Mine disaster

The Sago Mine disaster was a January 2, 2006 coal mine explosion near Tallmansville, West Virginia, that killed 12 of 29 trapped miners; Randal McCloy Jr. was the sole survivor.

Sago Mini

Sago Mini, also known as Sago Sago, is a Toronto-based studio that makes apps, toys, and subscriptions for preschool children, founded in 2001 and owned by Spin Master since 2016.

Sagrada Família

The Sagrada Família, also known as the Basílica de la Sagrada Família, is a Roman Catholic basilica in Barcelona designed mainly by Antoni Gaudí and still under construction.

Oct 22, 2026

Sagu

Sagu is a mourning poem, a kind of elegy, sung at the yuğ funeral ceremonies of pre-Islamic Turkic literature; its oldest surviving example is the 11th-century Alp Er Tunga Sagu.

Saguaro

Saguaro (Carnegiea gigantea, O'odham Ha:san), giant columnar cactus of the Sonoran Desert; grows only there, lives 150-175 years, reaches 50 feet, fruits used by Tohono O'odham.

Saguaro National Park

Saguaro National Park, near Tucson, Arizona, is a 1994 national park (monument since 1933) in two districts protecting over 2 million saguaro cacti across about 92,000 acres of Sonoran Desert.

Saguenay

Saguenay, Quebec: city created 18 February 2002 by merging Chicoutimi, Jonquière, La Baie, Laterrière, Lac-Kénogami, Shipshaw and part of Canton Tremblay; three boroughs, 151,972 residents (2025), aluminum and hydroelectric economy.

Saguenay Fjord National Park

Saguenay Fjord National Park (Parc national du Fjord-du-Saguenay) is a Sépaq provincial park in Quebec, created in 1983, protecting both banks of the 100 km Saguenay Fjord across 328.6 km2, with hiking, sea kayaking, via ferrata, and beluga-focused marine protections.