Aba Abacus Abaft Abbey Abbreviate Abbreviation Abdicate Abdomen Abduct Abecedarian Aberration Ablution Abnormal Abode Abomasum Abort Abortion Aboulia Abracadabra Abrasion Abridge Abscess Abseil Absinth Absolute Temperature Absorber Circuit Absorptiometer Abstract Acardia Accelerating Electrode Accelerating Grid Acceleration Accelerator Accelerator Valve Accelerometer Accent Accolade Accomplice Accordion Accounts Accumulator Ace Acetal Acetaminophen Acetic acid Acetic ether Acetone Acetylene Achor Acid ACK Aclinic Acne Aconitine Acorn Valve Acoustic Acoustic Feedback Acoustics Acre Acridine Acriflavine Acromegaly Acronym Acrophobia Acropolis Acrylic Act of Succession Actinide Actinium Actinometer Acts of Supremacy Adaptive Equalisation Adcock Aerial Adhesive Adipocere Adit Admiralty Adobe Adult Adytum Adze Aeon Aerial Aerodrome Afrikaans Agar Agenda Aggry Beads Agoraphobia Air Aircraft Aisle Albugo Alchemy Alcohol Alcoholic Aldehyde Ale Aleurometer Algebra Algebraic ALGOL Algorithm Alkali Alkaloid Alkane Alkanes Alkene Alkyl Allergy Alley Allies Alloy Alluvium Alpha Alpha Particles Alpha Rays Alpha-tocopherol Alphabet Altar Alternating Current Althing Altimeter Altitude Aluminium
An aba is a sack like garment worn by Arabs.
An abacus is a counting frame with balls sliding on wires. It was first used before the adoption of the ten digit numeric system and is still widely used in China.
Abaft means towards the rear of a ship.
An abbey is a body of monks or a monastic building.
Abbreviate means make shorter.
An abbreviation is a short form of a word or words.
Abdicate means to renounce one's thrown.
The abdomen is the part of a creature's body between diaphragm and pelvis.
Abduct means to take away by force or fraud.
The Abecedarian were the followers of Nicholas Storck, a 16th century German Anabaptist. They were so called because they rejected all worldly knowledge including learning the alphabet.
Aberration is another word for error.
Ablution is ceremonial washing.
Abnormal means deviating from normal.
Abode is a place where something lives.
An abomasum is the fourth stomach of a ruminant.
Abort means to terminate early.
Abortion is the expulsion of the foetus from the uterus.
In psychology aboulia is the loss of will.
Abracadabra is a qabbalistic magic word.
An abrasion is a sore place on the skin caused by rubbing.
Abridge means to shorten by condensing.
An abscess is a pus filled infection of an animal.
In mountaineering abseil means to descend using a rope.
Absinth is a strong alcoholic drink containing from 60 to 80 percent alcohol. It contains wormwood oil which gives it its distinctive taste, but also toxic qualities.
Absolute Temperature is temperature based on the absolute zero of temperature (-273 degrees Celsius or o degrees Kelvin) at which a body possesses no thermal energy.
In electronics, an absorber circuit is a combination of a resistor and a capacitor in series, connected across the terminals of a switch or other circuit-breaking device in an oscillatory circuit. Its function is to damp the circuit and thus to prevent sparking or arcing when the current is interrupted.
An absorptiometer is an instrument for the accurate measurement of the absorption and transmission of light by semi-transparent substances and used for the determination of turbidity, fluorimetry, etc.
Abstract means theoretical rather than practical.
Acardia is the condition of a person born without a heart.
An accelerating electrode is an electrode in an electron tube which is maintained at a positive potential with respect to the cathode and any other electrodes situated between the cathode and the accelerating electrode, thus imparting acceleration to electrons in the direction away from the cathode. Although this definition includes the anode of the tube, the term is usually reserved for accelerating electrodes other than the anode.
In electronics, an accelerating grid is an accelerating electrode in the form of a grid.
Acceleration is the rate at which a moving body increases in velocity.
An accelerator is a device for increasing speed.
An accelerator valve is a thermionic valve employed as a particle accelerator.
An accelerometer is an apparatus, either mechanical or electromechanical, for measuring acceleration or deceleration - that is, the rate of increase or decrease in the velocity of a moving object. Accelerometers are used to measure the efficiency of the braking systems on road and rail vehicles; those used in aircraft and spacecraft can determine accelerations in several directions simultaneously. There are also accelerometers for detecting vibrations in machinery.
An accent is a local mode of pronunciation in speech.
An accolade is a gentle blow on the shoulders with the flat of a sword given by a Sovereign or his representative in conferring knighthood to the recipient.
An accomplice is someone associated with somebody else in the committing of a crime.
An accordion is a small portable musical instrument with a keyboard and bellows. It was invented by Damian in 1829.
Accounts are a statement of income and expenditure.
In electrical terms, an accumulator stores electrical energy.
An ace is a playing card with one pip.
In tennis terms an ace is a non-returnable serve.
Acetal is a colourless liquid formed by oxidation of alcohol.
Acetaminophen is a drug used to treat mild pain or fever. It has the
possible side effects of: Rash, itching and severe liver damage with
over dosing.
Acetic acid is an organic acid with the formulae ch3cooh.
see "Ethyl Acetate"
Acetone is a colourless liquid with the formulae ch2coch3.
Acetylene is a highly inflammable gas of the hydrocarbon family used for welding and cutting metals.
Achor is (was?) a disease of infants, in which the head, face and breast become encrusted with thin, yellowish or greenish scabs.
An acid is a chemical compound that reacts with metals to form salts by releasing hydrogen.
In telecommunications, ACK is the "acknowledge" character in many data codes; used most commonly for an affirmative response of correct receipt.
The aclinic is a magnetic equator.
Acne is a skin eruption due to inflammation of the sebaceous glands.
Aconitine is a poisonous alkaloid derived from aconite.
An acron valve is a form of thermionic valve used at ultra-high frequencies, in which, by adopting very small dimensions and special constructions, the inter-electrode capacitances, lead inductances and transit time effects are greatly reduced.
The term acoustic refers to hearing.
Acoustic feedback is the return of acoustic energy from the output of a sound reproducing equipment, such as a microphone-amplifier-loudspeaker combination, to the input or to an intermediate stage, thereby causing the system to generate sustained oscillations which are manifested as continual howling.
see "acoustic"
An acre is a measurement of land area being 4840 square yards.
Acridine is an organic compound with the formulae c13h9n used in dyes and drugs.
Acriflavine is an antiseptic powder.
Acromegaly is a disease due to over activity of the pituitary gland results in excessive bone growth, especially the skull.
An acronym is a word formed from the initials of other words.
Acrophobia is the fear of high places.
The acropolis was the citadel of ancient Greek cities.
Acrylic is a synthetic fibre derived from acrylic acid.
The Act of Succession in 1534 declared the marriage of Henry VIII and Catherine of Aragon null and void, and settled the succession to the throne on the heirs of Henry VIII by Anne Boleyn.
An actinide is an element with an atomic number between 89 and 103.
Actinium is a radioactive element with the symbol Ac.
An actinometer is an instrument for measuring heat radiation.
The Acts of Supremacy were passed in 1534 enacting that the King (Henry VIII) was the only supreme head on earth of the Church of England, with power to redress all heresies and abuses.
Adaptive Equalisation is a telecommunications term referring to the equalisation of received digital signals capable of adjustment during actual transmission.
an Adcock aerial is a radio aerial system consisting of two vertical open-spaced dipoles with screened horizontal connections. It thus responds almost exclusively to the vertically polarised component of a received wave and is used for radio direction finding.
An adhesive is a sticky substance.
Adipocere is a substance in dead bodies formed by decomposition of fatty acids when exposed to moisture.
An adit is the horizontal entrance to a mine.
The admiralty was the board of state charged with the provision, organisation and control of the royal navy. It was founded by Henry VIII and amalgamated in 1964 into the ministry of defence.
An adobe is a Mexican house made of clay bricks.
An adult is a fully grown being.
An adytum is the inner most part of a temple.
An adze is a carpenter's tool for cutting away the surface of wood.
An aeon is an immeasurable period.
An aerial is a receiving or radiating device used in radio communications.
An aerodrome is a place where aircraft are based.
Afrikaans is a language used in the Republic of South Africa.
Agar is a laxative substance obtained from seaweed.
An agenda is a list of tasks.
Aggry Beads are glass beads prized by West African natives as ornaments and having magical and medicinal powers.
Agoraphobia is the fear of open spaces.
The air is a mixture of gasses enveloping the earth.
An aircraft is a flying machine, a vessel which flies through the air rather than floats on water or travels along a road or rail.
An aisle is a passage between rows of seats.
Albugo is an affection of the eye, consisting of a white opacity in the cornea.
Alchemy was the medieval forerunner to chemistry.
Alcohol is a volatile liquid derived from hydrocarbons.
see "alcohol"
Aldehyde is a chemistry term applied to the compounds of alcohol intermediate between the alcohols and the acids.
Ale is an alcoholic drink made from malt and hops.
An aleurometer is a device used in bread making for measuring the quality of wheaten flour.
Algebra is a division of mathematics dealing with relations.
see "algebra"
ALGOL is an algebraic computer language.
An algorithm is a set of rules.
An alkali is a chemical substance.
The alkaloids are nitrogenous organic substances.
The alkanes are the paraffin series of hydrocarbons.
see "alkane"
An alkene is a member of the ethylene series of hydrocarbons.
Alkyl refers to a substance which is derived from or related to the paraffin series of hydrocarbons.
An allergy is a hypersensitivity of body tissue to a substance.
An alley is a narrow street.
The Allies were various countries that fought the Axis forces in the Second World War.
An alloy is a mixture of a metal and other metals or non-metals.
Alluvium is river transported deposits of mud, sand and gravel which accumulate to form distinctive features such as levees, flood plains and deltas.
Alpha is the first letter of the Greek alphabet.
Alpha Particles are the nuclei of the atom of helium, comprising two neutrons and two protons, and thus exhibiting a positive electric charge.
Alpha Rays are a stream of swiftly moving alpha particles. An alpha ray is capable of ionizing gases and of producing fluorescence in certain substances.
see "Vitamin E"
An alphabet is an ordered series of letters used in language.
An altar is a block used for making offerings to a deity.
Alternating current is electric current which changes direction rhythmically, rising from zero to a maximum in the positive direction, falling to zero again and then increasing to a maximum in the negative direction before returning again to zero, after which the cycle repeats. The number of cycles per second is the frequency of the alternating phenomenon. British domestic alternating current exhibits 50 cycles per second, where as American domestic alternating current exhibits 60.
The althing is the parliament of Iceland, it was created in 930 and is the oldest parliamentary assembly in the world.
An altimeter is a device measuring altitude.
Altitude is height above mean sea level.
Aluminium is a light-weight silvery metal element with the symbol Al.