18-letter words containing o, a, s, t
- northern transvaal — province of South Africa, in the N part: 47,599 sq mi (123,280 sq km); pop. 5,202,000; cap. Pietersburg
- 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.
- not by a long shot — absolutely not
- not in a fit state — If you say that someone is not in a fit state to do something, you mean that they are too upset or ill to do it.
- notifiable disease — any one of a number of infectious diseases of humans and animals, that must be reported to the public health authorities
- nova scotia salmon — an Atlantic salmon, especially from the waters off Nova Scotia, cured in the local manner.
- 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.
- objective idealism — a form of idealism asserting that the act of experiencing has a reality combining and transcending the natures of the object experienced and of the mind of the observer.
- oblique-slip fault — a fault on which the movement is along both the strike and the dip of the fault
- oedipus at colonus — a tragedy by Sophocles, written toward the end of his life and produced posthumously in 401? b.c.
- 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
- official solicitor — an officer of the Supreme Court of Judicature with special responsibilities for protecting the interests of persons under disability
- offset lithography — offset (def 6).
- oil of catechumens — holy oil used in baptism, the ordination of a cleric, the coronation of a sovereign, or in the consecration of a church.
- old man of the sea — (in The Arabian Nights' Entertainments) an old man who clung to the shoulders of Sindbad the Sailor for many days and nights.
- on a sticky wicket — in an awkward situation
- on one's last legs — either of the two lower limbs of a biped, as a human being, or any of the paired limbs of an animal, arthropod, etc., that support and move the body.
- 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 danger list — critically ill in hospital
- one's heart bleeds — used to express sympathetic grief, but often used ironically
- one's native heath — the place of one's birth or childhood
- 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-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
- optical soundtrack — the final soundtrack on a motion picture, which appears as a band of black and white serrations along a strip of film to the left of the composite print. Light is shined through the serrations and is converted to audible sound.
- order of australia — an order awarded to Australians for outstanding achievement or for service to Australia or to humanity at large; established in 1975
- organic solidarity — social cohesiveness that is based on division of labor and interdependence and is characteristic of complex, industrial societies.
- 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
- orthotungstic acid — an oxyacid acid of tungsten. Formula: H2WO4
- oscillating engine — a steam engine having piston rods connected directly to the crankshaft and cylinders oscillating on trunnions.
- osteitis deformans — Paget's disease.
- osteogenic sarcoma — osteosarcoma
- osteoradionecrosis — bone tissue death induced by radiation.
- out of one's hands — no longer one's responsibility
- outer automorphism — an automorphism that is not an inner automorphism.
- ovariohysterectomy — Surgical removal of the ovaries and uterus.
- overdraft interest — interest charged on money withdrawn in excess of the credit balance of a bank or building society account
- overpressurization — pressure in excess of normal atmospheric pressure, as that caused by an explosion's shock wave or created in an accelerating airplane.