0%

22-letter words containing o, n, t

  • meeting of (the) minds — an agreement
  • memory management unit — (hardware, memory management)   (MMU, "Paged Memory Management Unit", PMMU) A hardware device or circuit that supports virtual memory and paging by translating virtual addresses into physical addresses. The virtual address space (the range of addresses used by the processor) is divided into pages, whose size is 2^N, usually a few kilobytes. The bottom N bits of the address (the offset within a page) are left unchanged. The upper address bits are the (virtual) page number. The MMU contains a page table which is indexed (possibly associatively) by the page number. Each page table entry (PTE) gives the physical page number corresponding to the virtual one. This is combined with the page offset to give the complete physical address. A PTE may also include information about whether the page has been written to, when it was last used (for a least recently used replacement algorithm), what kind of processes (user mode, supervisor mode) may read and write it, and whether it should be cached. It is possible that no physical memory (RAM) has been allocated to a given virtual page, in which case the MMU will signal a "page fault" to the CPU. The operating system will then try to find a spare page of RAM and set up a new PTE to map it to the requested virtual address. If no RAM is free it may be necessary to choose an existing page, using some replacement algorithm, and save it to disk (this is known as "paging"). There may also be a shortage of PTEs, in which case the OS will have to free one for the new mapping. In a multitasking system all processes compete for the use of memory and of the MMU. Some memory management architectures allow each process to have its own area or configuration of the page table, with a mechanism to switch between different mappings on a process switch. This means that all processes can have the same virtual address space rather than require load-time relocation. An MMU also solves the problem of fragmentation of memory. After blocks of memory have been allocated and freed, the free memory may become fragmented (discontinuous) so that the largest contiguous block of free memory may be much smaller than the total amount. With virtual memory, a contiguous range of virtual addresses can be mapped to several non-contiguous blocks of physical memory. In early designs memory management was performed by a separate integrated circuit such as the MC 68851 used with the Motorola 68020 CPU in the Macintosh II or the Z8015 used with the Zilog Z80 family of processors. Later CPUs such as the Motorola 68030 and the ZILOG Z280 have MMUs on the same IC as the CPU.
  • methyl isobutyl ketone — a colorless, slightly water-soluble, flammable liquid, C 6 H 1 2 O, having a pleasant odor: used as a solvent for nitrocellulose, gums, resins, fats, waxes, and oils.
  • million electron volts — a unit of energy equal to the energy acquired by an electron in falling through a potential of 10 6 volts. Abbreviation: MeV .
  • mistress of ceremonies — a woman who directs the entertainment at a party, dinner, or the like.
  • molecular distillation — a vacuum distillation in which the molecules of the distillate reach the condenser before colliding with one another.
  • monoammonium phosphate — a white, crystalline, moderately water-soluble compound, NH 4 H 2 PO 4 , used as fertilizer, in fire extinguishers, etc.
  • most significant digit — the digit farthest to the left in a number. Abbreviation: MSD.
  • mother carey's chicken — any of various small petrels, especially the stormy petrel, Oceanites oceanicus.
  • motorcycle combination — a motorcycle with a sidecar attached
  • motoring correspondent — a journalist who reviews and writes about cars
  • mountain standard time — one of the standard times used in North America, seven hours behind Greenwich Mean Time
  • much ado about nothing — a comedy (1598?) by Shakespeare.
  • mutton dressed as lamb — If you describe a woman as mutton dressed as lamb, you are criticizing her for trying to look younger than she really is, in a way that you consider unattractive.
  • myalgic encephalopathy — a condition characterized by painful muscles, extreme fatigue, and general debility, sometimes occurring as a sequel to viral illness
  • nassella tussock board — one of many local statutory organizations set up in different regions of New Zealand to eradicate the invasive nassella tussock weed
  • national semiconductor — (company)   A semiconductor manufacturer, responsible for the SC/MP, National Semiconductor 16000 and National Semiconductor 32000 series of microprocessors.
  • natural classification — classification of organisms according to relationships based on descent from a common ancestor
  • navigational satellite — a satellite designed to enable operators of aircraft, vehicles, or vessels to determine their geographical position.
  • negative hallucination — an apparent abnormal inability to perceive an object
  • negative reinforcement — form of conditioning
  • neither here nor there — in this place; in this spot or locality (opposed to there): Put the pen here.
  • network interface card — network interface controller
  • network node interface — (networking)   (NNI) The ATM Forum's specification for connections between network nodes. NNI makes network routing possible. It typically refers to backbone trunk connections between ATM switching equipment. See also: UNI.
  • new zealand greenstone — a variety of nephrite from New Zealand, used as a gemstone
  • newton's law of motion — any of three laws of classical mechanics, either the law that a body remains at rest or in motion with a constant velocity unless an external force acts on the body (first law of motion) the law that the sum of the forces acting on a body is equal to the product of the mass of the body and the acceleration produced by the forces, with motion in the direction of the resultant of the forces (second law of motion) or the law that for every force acting on a body, the body exerts a force having equal magnitude and the opposite direction along the same line of action as the original force (third law of motion or law of action and reaction)
  • nigger in the woodpile — a hidden snag or hindrance
  • nitrohydrochloric acid — aqua regia.
  • no room to swing a cat — If you say 'There's no room to swing a cat' or 'You can't swing a cat', you mean that the place you are talking about is very small or crowded.
  • nodal switching system — (NSS) Main routing nodes in the NSFnet backbone.
  • nominal semidestructor — (abuse)   Slang for "National Semiconductor", found among other places in the 4.3BSD networking sources. During the late 1970s to mid-1980s this company marketed a series of microprocessors including the National Semiconductor 16000 and National Semiconductor 32000. At one point early in the great microprocessor race, the specs on these chips made them look like serious competition for the rising Intel 80x86 and Motorola 680x0 series. Unfortunately, the actual parts were notoriously flaky and never implemented the full instruction set promised in their literature, apparently because the company couldn't get any of the mask steppings to work as designed. They eventually sank without trace, joining the Zilog Z8000 and a few even more obscure also-rans in the graveyard of forgotten microprocessors.
  • non-constructive proof — (logic)   (Or "existence proof") A proof that something exists that does not provide an example of that thing or a method for finding an example. (A constructive proof does provide such an example or method). For example, for any pair of finite real numbers n < 0 and p > 0 there exists a real number 0 < k < 1 such that f(k) = (1-k)*n + k*p = 0. A non-constructive proof might proceed by observing that as k changes continuously from 0 to 1, f(k) changes continuously from n to p and, since they lie either side of zero, f(k) must pass through zero for some intermediate value of k. This proof does not tell us what that value of k is, only that it exists.
  • non-euclidean geometry — geometry based upon one or more postulates that differ from those of Euclid, especially from the postulate that only one line may be drawn through a given point parallel to a given line.
  • non-maskable interrupt — (NMI) An IRQ 7 on the PDP-11 or 680x0 or the NMI line on an 80x86. In contrast with a priority interrupt (which might be ignored, although that is unlikely), an NMI is *never* ignored.
  • non-restrictive clause — a relative clause that describes or supplements but is not essential in establishing the identity of the antecedent and is usually set off by commas in English. In This year, which has been dry, is bad for crops the clause which has been dry is a nonrestrictive clause.
  • nondestructive testing — any of several methods of detecting flaws in metals without causing damage. The most common techniques involve the use of X-rays, gamma rays, and ultrasonic vibrations
  • nonmonetary advantages — the beneficial aspects of an employment, such as the stimulation of the work, attractiveness of the workplace, or its nearness to one's home, that do not reflect its financial remuneration
  • nonrepresentationalism — not resembling or portraying any object in physical nature: a nonrepresentational painting.
  • nonspecific urethritis — nongonococcal urethritis.
  • nonspecular reflection — the diffuse reflection of sound or light waves
  • nonterminating decimal — a decimal numeral that does not end in an infinite sequence of zeros (contrasted with terminating decimal).
  • normal order reduction — Under this evaluation strategy an expression is evaluated by reducing the leftmost outermost redex first. This method will terminate for any expression for which termination is possible, whereas applicative order reduction may not. This method is equivalent to passing arguments unevaluated because arguments are initially to the right of functions applied to them. See also computational adequacy theorem.
  • north atlantic current — an ocean current flowing NE toward the British Isles, formed by the convergence of the Gulf Stream and the Labrador Current SE of Newfoundland.
  • north rhine-westphalia — a state in W Germany; formerly a part of Rhine province. 13,154 sq. mi. (34,070 sq. km). Capital: Düsseldorf.
  • northern corn rootworm — corn rootworm.
  • northern redbelly dace — any of the small, brightly colored North American freshwater cyprinids, especially Phoxinus oreas (northern redbelly dace) and P. erythrogaster (southern redbelly dace)
  • not be sb's department — If you say that a task or area of knowledge is not your department, you mean that you are not responsible for it or do not know much about it.
  • oak processionary moth — a moth, (Thaumetopoea processionea), of the family Thaumetopoeidae, the larvae of which leave the communal shelter nightly for food in a V-shaped procession
  • object-oriented design — (programming)   (OOD) A design method in which a system is modelled as a collection of cooperating objects and individual objects are treated as instances of a class within a class hierarchy. Four stages can be identified: identify the classes and objects, identify their semantics, identify their relationships and specify class and object interfaces and implementation. Object-oriented design is one of the stages of object-oriented programming.
  • object-oriented pascal — Object Pascal
Was this page helpful?
Yes No
Thank you for your feedback! Tell your friends about this page
Tell us why?