18-letter words containing e, s, r, o
- nord-pas-de-calais — a region of N France, on the Straits of Dover (the Pas de Calais): coal-mining, textile, and metallurgical industries
- normally aspirated — A normally aspirated or naturally aspirated engine breathes air at atmospheric pressure.
- north bedfordshire — a city in Bedfordshire, in central England.
- north lincolnshire — a unitary authority of NE England, in Lincolnshire: formerly (1975–96) part of the county of Humberside. Pop: 155 000 (2003 est). Area: 1497 sq km (578 sq miles)
- north saskatchewan — a river in S central Canada, flowing E from the Rocky Mountains and joining the South Saskatchewan River to form the Saskatchewan River. 760 miles (1223 km) long.
- north truchas peak — a mountain in N New Mexico, near Santa Fe: one of the three Truchas Peaks. 13,110 feet (3999 meters).
- northeast by north — a point on the compass 11°15′ north of northeast. Abbreviation: NEbN.
- northeast corridor — the long, narrow strip of land between Boston, New York City, and Washington, D.C., containing many adjacent urban areas.
- northern cameroons — German Kamerun. a region in W Africa: a German protectorate 1884–1919; divided in 1919 into British and French mandates.
- northern transvaal — province of South Africa, in the N part: 47,599 sq mi (123,280 sq km); pop. 5,202,000; cap. Pietersburg
- northwest by north — a point on the compass, 11°15′ north of northwest. Abbreviation: NWbN.
- not a pretty sight — If you say that someone or something is not a pretty sight, you mean that it is not pleasant to look at.
- nueva san salvador — Santa Tecla.
- nurse practitioner — a registered nurse who has received special training for diagnosing and treating routine or minor ailments. Abbreviation: NP.
- nurse-practitioner — a registered nurse who has received special training for diagnosing and treating routine or minor ailments. Abbreviation: NP.
- off-street parking — spaces for cars located on private property rather than on a public street
- offensive material — any published or broadcast content (such as articles, photographs, films, or websites) that is likely to be upsetting, insulting, or objectionable to some or most people
- office of readings — the first of the canonical hours; matins
- offset lithography — offset (def 6).
- on everyone's lips — being much discussed
- on that/this score — You can use on that score or on this score to refer to something that has just been mentioned, especially an area of difficulty or concern.
- on the credit side — You say on the credit side in order to introduce one or more good things about a situation or person, usually when you have already mentioned the bad things about them.
- on the danger list — critically ill in hospital
- on the strength of — the quality or state of being strong; bodily or muscular power; vigor.
- on your conscience — If you have something on your conscience, you feel guilty because you know you have done something wrong.
- one of sb's number — One of your number is a member of your group.
- one's heart bleeds — used to express sympathetic grief, but often used ironically
- one's number is up — one is finished; one is ruined or about to die
- open heart surgery — surgery performed on the exposed heart while a heart-lung machine pumps and oxygenates the blood and diverts it from the heart.
- open pandora's box — If someone or something opens Pandora's box or opens a Pandora's box, they do something that causes a lot of problems to appear that did not exist or were not known about before.
- open-heart surgery — surgery performed on the exposed heart while a heart-lung machine pumps and oxygenates the blood and diverts it from the heart.
- operating expenses — Operating expenses are expenses related to carrying out normal business activities.
- operating software — software used in the operation of a computer system, typically by performing such tasks as memory allocation, job scheduling, and input/output control
- operationalisation — Alternative spelling of operationalization.
- operations manager — business director
- optical disc drive — optical disk drive
- optical disk drive — (hardware) (Or "optical disc drive", "optical storage") A generic term for any device that reads and/or writes optical media, i.e. compact discs, DVDs and/or Blu-ray discs or future media that uses light (from a small laser) to read data off a removable, rotating disk. At least one such drive is commonly installed in most personal computers to allow them to play and/or record audio and video media and load and store data such as program installers. The floppy disk has been replaced by optical media due to its vastly greater capacity, e.g. 50,000 megabytes for a dual-layer blu-ray disc compared with 1.5 megabytes for a floppy (over 30,000 times as much).
- optical microscope — traditional magnifying instrument
- order of australia — an order awarded to Australians for outstanding achievement or for service to Australia or to humanity at large; established in 1975
- order room service — When a customer orders room service, they ask for meals or drinks to be brought to their room.
- oriental alabaster — alabaster (def 2).
- oriental cat's-eye — a chatoyant variety of chrysoberyl, used as a gem.
- oriental scops owl — any of a group of small owls having ear tufts and a whistling call, especially Otus scops (Old World scops owl) and O. sunia (Oriental scops owl)
- oriental shorthair — any of a breed of domestic cat, similar to the Siamese but with greenish eyes and often a coat of a solid color
- orientation course — induction into sth
- orthopedic surgery — corrective operation on bones or joints
- osteitis deformans — Paget's disease.
- osteogenic sarcoma — osteosarcoma
- osteoradionecrosis — bone tissue death induced by radiation.
- outer automorphism — an automorphism that is not an inner automorphism.