20-letter words containing o, d, r, a
- macular degeneration — degeneration of the central portion of the retina, resulting in a loss of sharp vision.
- magnetohydrodynamics — the branch of physics that deals with the motion of electrically conductive fluids, especially plasmas, in magnetic fields. Abbreviation: MHD.
- mail exchange record — (messaging) (MX Record) A DNS resource record type that says which SMTP server handles electronic mail for a particular domain. E.g. the MX record foo.co.uk. 1054 IN MX 10 mail.foo.co.uk. means that mail for an address like "[email protected]" should be sent to "mail.foo.co.uk". There can be several servers for a domain. The "10" is a priority - the server with the lowest number will be tried first.
- mail-order catalogue — a catalogue of goods you can buy from a particular company by mail order
- make a/no difference — If something makes a difference or makes a lot of difference, it affects you and helps you in what you are doing. If something makes no difference, it does not have any effect on what you are doing.
- make head (n)or tail — If you say that you cannot make head nor tail of something or you cannot make head or tail of it, you are emphasizing that you cannot understand it at all.
- make head or tail of — to attempt to understand (a problem, etc)
- margaret of scotland — Saint. 1045–93, queen consort of Malcolm III of Scotland. Her piety and benefactions to the church led to her canonization (1250). Feast days: June 10, Nov 16
- maternal deprivation — the lack of a mother in a child's life, considered a cause of psychological problems later in life
- media access control — (networking) (MAC) The lower sublayer of the OSI data link layer. The interface between a node's Logical Link Control and the network's physical layer. The MAC differs for various physical media. See also MAC Address, Ethernet, IEEE 802.3, token ring.
- medical practitioner — doctor
- medieval warm period — the time, c900–1400, during which warmer temperatures existed in many parts of the world. Abbreviation: MWP.
- megabytes per second — (unit) (MBps, MB/s) Millions of bytes per second. A unit of data rate. 1 MB/s = 1,000,000 bytes per second (not 1,048,576).
- memory address space — (architecture) 1. Any part of a processor's address space that is occupied by memory. 2. The range of addresses seen by a memory device relative to the base address at which it is mapped into the processor's address space.
- meta-dichlorobenzene — a colorless liquid, C 6 H 4 Cl 2 , soluble in alcohol and ether: used as a fumigant and insecticide.
- microwave background — a background of microwave electromagnetic radiation with a black-body spectrum discovered in 1965, understood to be the thermal remnant of the big bang with which the universe began
- modify a reservation — If you modify a reservation, you change a detail of a booking because someone who has booked a room has asked you to.
- motor neuron disease — Motor neuron disease is a disease which destroys the part of a person's nervous system that controls movement.
- mpeg-1 audio layer 1 — (audio, compression, algorithm) (MP1) A simple 32-subband audio compressor using a floating point representation for subband samples. Resolution and scale factor are stored for groups of 12 subsamples. MP1 is only used for Philips DCC Digital Compact cassette with data rates of 384 kbps.
- mpeg-1 audio layer 3 — (music, file format) (MP3) A digital audio compression algorithm that acheives a compression factor of about twelve while preserving sound quality. It does this by optimising the compression according to the range of sound that people can actually hear. MP3 is currently (July 1999) the most powerful algorithm in a series of audio encoding standards developed under the sponsorship of the Moving Picture Experts Group (MPEG) and formalised by the International Organization for Standardization (ISO). MP3 is very different from Layer 2, using an additional MDCT layer to increase frequency resolution. Its scale factor groups are more optimised for the human ear, and it uses nonlinear sample quantisation and Huffman coding. MP3 files (filename extension ".mp3") can be downloaded from many websites and can be played using software available for most operating systems (also downloadable), e.g. Winamp for PC, MacAmp for Macintosh, and mpeg123 for Unix. MP3 files are usually downloaded completely before playing but streaming MP3 is also possible. A program called a "ripper" can be used to copy a selection from a music CD onto your hard disk and another program called an encoder can convert it to an MP3 file.
- mpeg-2 audio layer 3 — (compression, standard, algorithm, file format) An extention of MPEG-1 audio layer 3 for lower sampling rates (16-24 kHz) targeting bit rates from 32-64 kbps (possibly 8-160 kbps). It is often combined with MPEG-2 LSF.
- multistep hydroplane — a motorship having a flat bottom built as a series of planes inclined forward, the ship planing on each from stem to stern as its speed increases.
- mum-and-dad investor — a small-scale non-professional investor
- neighbourhood warden — a person employed by a local authority to patrol residential areas and deal with antisocial behaviour
- nemine contradicente — no one contradicting; unanimously.
- net national product — the gross national product less allowance for depreciation of capital goods. Abbreviation: NNP.
- new democratic party — the Canadian social democratic party formed in 1961
- nonaccidental injury — damage, such as a bruise, burn, or fracture, deliberately inflicted on a child or an old person
- nondirective therapy — client-centered therapy.
- nonrepeating decimal — a decimal representation of any irrational number, having the property that no sequence of digits is repeated ad infinitum.
- north atlantic drift — 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 canadian river — a river in NE New Mexico, E Texas, and E Oklahoma, flowing SE to the Canadian River. 760 miles (1223 km) long.
- north richland hills — a town in N Texas.
- northern white cedar — any of several chiefly coniferous trees valued for their wood, especially Chamaecyparis thyoides, of the eastern U.S., or Thuja occidentalis (northern white cedar) of northeastern North America.
- not worth the candle — not worth the price or trouble entailed (esp in the phrase the game's not worth the candle)
- notre dame mountains — a mountain range in E Quebec, Canada, an extension of the Green Mountains in Vermont and a portion of the Appalachian Mountains: about 500 miles (800 km) long, rising about 2000 feet (610 meters).
- ode on a grecian urn — a poem (1819) by Keats.
- officer of the guard — an officer, acting under the officer of the day, who is responsible for the instruction, discipline, and performance of duty of the guard in a post, camp, or station. Abbreviation: OG, O.G.
- on the drawing board — in the planning stage
- on the starboard bow — within 45 degrees to the starboard of straight ahead
- one's heart's desire — If you say that someone or something is your heart's desire, you mean that you want that person or thing very much.
- operant conditioning — conditioning (def 1).
- operating conditions — Operating conditions are a set of conditions for operating a particular system or process.
- operational database — (database) A database containing up-to-date, modifiable data, in contrast to a decision support database.
- operator overloading — overloading
- ophthalmodynamometer — a device for determining the nearest point of ocular convergence.
- optical mark reading — the reading of marks by an optical device whereby the information can be stored in machine-readable form
- order bill of lading — a bill of lading that is issued to the order of a shipper or consignee for delivery of the goods and that can be transferred by endorsement to third parties.
- orthopaedic mattress — a specially firm mattress designed to help correct or ameliorate the discomfort of disorders of the spine and joints
- orthophosphoric acid — a colorless, crystalline solid, H 3 PO 4 , the tribasic acid of pentavalent phosphorus: used chiefly in fertilizers, as a source of phosphorus salts, and in soft drinks as an acidulant and flavoring agent.