#eros
- Aberroscope — An optical instrument or diagnostic device historically used, or applied in biophysics experiments, for observing, visualizing, and qualitatively assessing spherical and chromatic aberrations of the eye or a lens system. The device typically employs a shaded micrometric grid (aberroscopic grid) through which a light beam passes, allowing the examiner or the patient to directly perceive geometric distortions on the retina or a projection screen.
- Ablation — A non-medical process of removal, reduction, or melting of material from the surface of a solid body through mechanical, thermal, or climatic actions. In glaciology, it represents the total loss of ice or snow from a glacier through melting, evaporation, or sublimation; in astronomy and aeronautics, it denotes the erosion of the protective layer of a meteorite or spacecraft entering the atmosphere due to intense thermal friction.
- Geological ablation — A conceptual form or terminological variant of 'ablație', used in classical geomorphology to describe the phenomenon of removal, washing away, or baring of rocks under the action of external agents (wind, flowing waters, waves). In soil dynamics, the term emphasizes the initial transport phase of fine detrital materials before they are deposited in sedimentary basins.
- Abrasion — A complex process of mechanical wearing down, erosion, grinding, or polishing of a solid surface (rocks, metals, industrial materials) through repeated friction with hard particles or abrasive bodies; (in geology) the destructive erosive action on sea or large lake shores exerted by the violent movement of waves and transported debris; (in medicine/dentistry) progressive pathological loss of hard dental substance or skin tissue (superficial scratch, graze) caused by external mechanical frictional factors.
- Acroscleroderma — A localized clinical form or initial stage of systemic sclerosis (scleroderma), characterized by the thickening, induration, and progressive loss of skin elasticity restricted to the distal extremities (hands, feet) and the face. This structural autoimmune process alters microcirculation and dermal connective tissue, being almost constantly associated with Raynaud's phenomenon, painful digital tip ulcers, sclerodactyly, and facial tightening.
- Acrosclerosis — An indurative pathological process or condition characterized by the sclerosis, thickening, and hardening of the connective tissue and skin at the distal extremities of the limbs (digits, hands) and the face, appearing as a major manifestation within limited systemic scleroderma. The term is often used interchangeably with acroscleroderma, structurally highlighting the dense fibrosis and tightening of periarticular and dermal collagen.
- Adamantolysis — A pathological or experimental process of destruction, dissolution, or structural disintegration of dental enamel, caused by the action of acids, bacterial enzymes, or severe metabolic disorders. This phenomenon leads to the demineralization of the enamel prism and the loss of tooth surface integrity, being the first stage in the development of deep carious lesions.
- Adenosclerosis — The pathological induration or hardening of a gland or a lymph node, caused by the progressive replacement of functional parenchymal tissue with fibrous connective tissue. This structural phenomenon occurs as a result of chronic inflammatory processes, local vascular disorders, or senile involution, leading to a reduced secretory or filtering capacity of the affected organ.
- Amphibious aircraft — Capable of operating, taking off, landing, or moving with equal efficiency both in the air and on the surface of water or solid ground. As a noun, it designates a seaplane equipped with a retractable wheeled landing gear, allowing it to use terrestrial airfields as easily as natural water runways.
- Airbase — A military airbase or a large aeronautical complex comprising airfields, takeoff and landing runways, hangars, repair shops, fuel and ammunition depots, as well as the logistical infrastructure necessary for the stationing, maintenance, and operation of military or commercial aircraft.
- Aerobioscope — A laboratory apparatus used for collecting, filtering, and determining the number of microorganisms (bacteria, fungal spores) present in a specific volume of air. This device operates by bubbling air through a sterile liquid or by impacting particles onto a solid culture medium, being essential for air hygiene monitoring in hospitals, laboratories, and pharmaceutical industries.
- Aerocell — A porous, insulating, and ultra-light material characterized by a cellular structure in which the liquid phase of a gel has been completely replaced with a gas (usually air) without the solid network collapsing. It is widely used in industrial thermal insulation, the aerospace industry, and construction due to its extremely low thermal conductivity.
- Aero club — A sports association, club, or aeronautical organization aimed at promoting, practicing, and developing recreational flight activities, piloting, skydiving, gliding, or aeromodelling. The term also designates the material base of such an association, including the airfield, hangars, aircraft, and training facilities.
- Aerospace — Relating simultaneously to airspace (atmospheric) and cosmic space (extra-atmospheric); located within these spaces or adapted to operate in both environments. The term describes technologies, vehicles, research missions, or related industries that integrate classical aviation and orbital or interplanetary spaceflight.
- Aerodyne — Any aircraft heavier than air, whose support and lift in the Earth's atmosphere are provided exclusively by the dynamic forces exerted by air on its lifting surfaces (fixed wings or moving rotors) during travel. The classification includes airplanes, helicopters, gliders, and drones, representing the opposite of aerostats.
- Aerodynamics — A branch of fluid mechanics that studies the laws governing the motion of air or other gases, as well as the forces exerted by them on solid bodies in relative motion to them. This scientific field governs the design of aircraft, rockets, and terrestrial vehicles by optimizing lift and drag forces.
- Aerodynamicist — An engineer or researcher specialized in the field of aerodynamics; a specialist who deals with the study, design, optimization, and testing of the behavior of solid bodies (aircraft, cars, rockets) moving through airflows or gases. This activity includes the use of advanced computer simulations and experimental tests in wind tunnels to reduce drag resistance.
- Aerodrome craft — An archaic, rare, or conceptual technical term used to describe an experimental heavier-than-air aircraft, an early prototype of a self-propelled airplane, or a covered dome-shaped structure designed for sheltering and protecting flight machines inside an airfield.
- Aerodontalgia — A pathophysiological disorder manifested by an acute, violent, and sudden toothache, directly triggered by variations in barometric pressure during high-altitude flight; it occurs due to the expansion of air or gases trapped underneath poorly fitted fillings or within deep untreated cavities.
- Avionics — A specialized branch of applied electronics and aeronautical engineering dealing with the design, manufacturing, installation, and maintenance of electronic systems and equipment used on board aircraft and rockets (navigation systems, communications, autopilot, radars, and cockpit sensors).