ETYM Latin apertura, from aperire. Related to Aperient.
1. An opening in something.
2. An opening; usually small.
3. Controls amount of light admitted.
In photography, an opening in the camera that allows light to pass through the lens to strike the film. Controlled by shutter speed and the iris diaphragm, it can be set mechanically or electronically at various diameters. + prikaži više

ETYM French arc, Latin arcus bow, arc. Related to Arch.
(Homonym: ark).
1. A continuous portion of a circle.
2. Any substance forming the shape of a curve or incomplete circle.

(Irregular plural: arches).
1. (Architecture) A masonry construction (usually curved) for spanning an opening and supporting the weight above it.
2. A curved bony structure supporting or enclosing organs (especially arches of the feet).
3. A curved shape in the vertical plane that spans an opening.
4. A passageway under an arch; SYN. archway. + prikaži više

1. A circular segment of a curve:; SYN. crook, turn.
2. Curved segment; SYN. curve.
3. Diagonal line traversing a shield from the upper right corner to the lower left; SYN. bend dexter.
4. The act of bending something; SYN. bending, flex, flexion, flection, inflection.

(Homonym: beau)
(Homonym: bow )
1. (Pronounced boh) A decorative interlacing of ribbons.
2. (Pronounced boh) A knot with two loops and loose ends; used to tie shoelaces; SYN. bowknot.
3. (Pronounced boh) A slightly curved piece of resilient wood with taut horsehair strands, used in playing certain stringed instrument.
4. (Pronounced boh) Curved piece of resilient wood with taut cord to propel arrows.
5. An appearance by actors or performers at the end of the concert or play in order to acknowledge the applause of the audience; SYN. curtain call.
6. Bending the head or body or knee as a sign of reverence or submission or shame; SYN. bowing, obeisance.
7. Front part of a vessel or aircraft; SYN. fore, prow, stem.
8. Something curved in shape; SYN. arc. + prikaži više

(Homonym: break).
1. Device used to slow or stop a vehicle.
2. A toothed instrument or machine for separating out the fiber of flax or hemp by breaking up the woody parts.
3. A machine for bending, flanging, folding, and forming sheet metal.
Device used to slow down or stop the movement of a moving body or vehicle. The mechanically applied caliper brake used on bicycles uses a scissor action to press hard rubber blocks against the wheel rim. The main braking system of an automobile works hydraulically: when the driver depresses the brake pedal, liquid pressure forces pistons to apply brakes on each wheel.
Two types of automobile brakes are used. Disc brakes are used on the front wheels of some automobiles and on all wheels of sports and performance automobiles, since they are the more efficient and less prone to fading (losing their braking power) when they get hot. Braking pressure forces brake pads against both sides of a steel disc that rotates with the wheel. Drum brakes are fitted on the rear wheels of some automobiles and on all wheels of some passenger automobiles. Braking pressure forces brake shoes to expand outward into contact with a drum rotating with the wheels. The brake pads and shoes have a tough friction lining that grips well and withstands wear.
Many trucks and trains have air brakes, which work by compressed air. On landing, jet planes reverse the thrust of their engines to reduce their speed quickly. Space vehicles use retrorockets for braking in space and use the air resistance, or drag of the atmosphere, to slow down when they return to Earth. + prikaži više

ETYM French compas, from Late Lat. compassus circle, prop., a stepping together; com- + passus pace, step. Related to Pace, Pass.
(Irregular plural: compasses).
1. An indicator points to the north.
2. The limit of capability; SYN. range, reach, grasp.
3. Used for drawing circles.
Any instrument for finding direction. The most commonly used is a magnetic compass, consisting of a thin piece of magnetic material with the north-seeking pole indicated, free to rotate on a pivot and mounted on a compass card on which the points of the compass are marked. When the compass is properly adjusted and used, the north-seeking pole will point to the magnetic north, from which true north can be found from tables of magnetic corrections.
Compasses not dependent on the magnet are gyrocompasses, dependent on the gyroscope, and radiocompasses, dependent on the use of radio. These are unaffected by the presence of iron and by magnetic anomalies of the Earth's magnetic field, and are widely used in ships and aircraft. See navigation.
A compass (or pair of compasses) is also an instrument used for drawing circles or taking measurements, consisting of a pair of pointed legs connected by a central pivot. + prikaži više

ETYM Latin concavitas: cf. French concavité. Related to Concave.
The property possessed by a concave shape; SYN. concaveness.

In geometry, the locus of a point moving according to specified conditions. The circle is the locus of all points equidistant from a given point (the center). Other common geometrical curves are the ellipse, parabola, and hyperbola, which are also produced when a cone is cut by a plane at different angles.
Many curves have been invented for the solution of special problems in geometry and mechanics—for example, the cissoid (the inverse of a parabola) and the cycloid.
1. A baseball thrown with spin so that its path curves as it approach the batter; SYN. curve ball, breaking ball, bender.
2. A line on a graph representing data.
3. The trace of a point whose direction of motion changes; SYN. curved shape. + prikaži više

Long-bow.
A powerful wooden bow drawn by hand; usually 5-6 feet long; used in medieval England.

ETYM as. spann; akin to Dutch span, Old High Germ. spanna, German spanne, Icel. spönn. Related to Span.
1. A unit of length based on the width of the expanded human hand (usually taken as 9 inches).
2. The complete duration of something.
3. The distance or interval between two points.
The algebraic difference between the limits of the range from zero to full scale. + prikaži više

Large genus of perennial and biennial pungent bulbous plants: garlic; leek; onion; chive; sometimes placed in family Alliacea as the type genus; Also called: genus Allium.
Genus of plants belonging to the lily family Liliaceae. Members of the genus are usually strong-smelling with a sharp taste, but form bulbs in which sugar is stored. Cultivated species include onion, garlic, chive, and leek. + prikaži više

ETYM Latin bulbus, Greek bolbos: cf. French bulbe.
1. A modified bud consisting of a thickened globular underground stem serving as a reproductive structure.
2. A rounded dilation or expansion in a canal or vessel or organ.
3. A rounded part of a cylindrical instrument (usually at one end).
Underground bud with fleshy leaves containing a reserve food supply and with roots growing from its base. Bulbs function in vegetative reproduction and are characteristic of many monocotyledonous plants such as the daffodil, snowdrop, and onion. Bulbs are grown on a commercial scale in temperate countries, such as England and the Netherlands. + prikaži više

ETYM French ognon, from Latin unio oneness, unity, a single large pearl, an onion. Related to One, Union.
1. Bulbous plant having hollow leaves cultivated worldwide for its rounded edible bulb; SYN. onion plant, Allium cepa.
2. Edible bulb of an onion plant.
3. Pungent bulb.
Bulbous plant Allium cepa of the lily family Liliaceae. Cultivated from ancient times, it may have originated in Asia. The edible part is the bulb, containing an acrid volatile oil and having a strong flavor.
The onion is a biennial, the common variety producing a bulb in the first season and seeds in the second. + prikaži više

1. Physical appearance
2. The act of directing the eyes toward something and perceiving it visually; SYN. looking, looking at.