#structural

• Atriocommissuropexy — A complex and rare surgical procedure consisting of the operative fixation of a cardiac valvular commissure to the atrial wall, utilized for the structural correction of congenital malformations or severe valvular insufficiencies. This technical reconstruction method aims to restore normal blood flow dynamics and prevent parasitic intracardiac regurgitation.
• Atriomegaly — Abnormal, pathological, and permanent enlargement of the volume or dimensions of one or both cardiac atria, usually caused by chronic pressure or volume overload. This structural alteration is frequently associated with valvular stenosis or insufficiency (mitral or tricuspid) and predisposes the patient to the onset of severe cardiac rhythm disorders, such as atrial fibrillation.
• Atrioseptopexy — A corrective surgical intervention consisting of the operative fixation or anchoring of the interatrial septum to correct a congenital structural defect, anatomical displacement, or septal instability. This surgical procedure restores the structural integrity of the dividing wall between the two atria, preventing abnormal mixing of arterial and venous blood.
• Atriotomy — A surgical incision made into the muscular wall of a cardiac atrium, performed to allow direct access inside the upper chambers of the heart for treating valvular or septal disorders, or for removing thrombi. This highly precise structural section requires, in most cases, the use of a cardiopulmonary bypass machine.
• Atriplex — A genus of herbaceous or shrubby plants in the family Amaranthaceae (formerly Chenopodiaceae), resistant to drought and salinity, popularly known as saltbush or orache. These species exhibit a complex adaptive structure, with leaves often covered with grayish hairs, and some are cultivated as edible vegetables or forage plants due to their high nutritional value.
• Saddening — The act of becoming sad or causing sadness and its result; the psychological process through which a person transitions into a state of temporary grief, sorrow, or depression. It represents the structural manifestation of a melancholic feeling triggered by internal or external factors, often reflected through changes in social behavior and facial expression.
• Attrition — A structural process of wear, grinding, or progressive numerical reduction; in dentistry, it represents the physiological or pathological wear of hard dental tissues through direct tooth-to-tooth friction; in geology, it describes the rounding of rock fragments through mutual friction during transport; in management, it refers to the natural loss of personnel (via retirements or resignations) without immediate replacement.
• Atrium — An unadapted form or architectural neologism often used as a variant for 'atriu'; the central open space of an ancient Roman house (domus), surrounded by rooms, having a central basin (impluvium) for collecting rainwater. In contemporary structural design, it describes a glass-covered interior courtyard located at the center of hotel complexes, office buildings, or large museums.
• Atrocity — An act of extreme cruelty, savage or inhuman character of an action; a terrible wickedness usually committed during wartime or under tyrannical regimes. It represents the structural manifestation of human barbarism, materialized through brutal violence, grave abuses, or deliberate destruction of human lives.
• Atrophic — A rare medical term or regressive form used to describe an organism, tissue, or individual affected by atrophy; lacking normal development, reduced in volume, or structurally degenerated due to lack of nutrition or activity. In modern standard terminology, it is used almost exclusively as a combining form or as the full adjective 'atrofiat'.
• Atrophy — To undergo a reduction in volume, weight, and functional capacity of an organ, tissue, or the entire body, due to malnutrition, prolonged lack of activity, or aging; (figuratively) to diminish, weaken, or lose original vigor, intensity, or structural value (such as the wasting of talent or feelings).
• Atrophying — Causing or accelerating the process of atrophy; a toxic, degenerative, or pathological factor that leads to a structural diminution of the volume and functional capacity of a tissue or organ. In clinical terms, it describes the destructive evolution of certain dermatological, muscular, or neurological conditions that leave behind tissue underdevelopment sequelae.
• Atrophying — The act of atrophying and its result; the biological or pathological process through which an organ or tissue gradually reduces its volume, weight, and functional capacities. Figuratively, it represents the progressive loss of vigor, intensity, or efficiency of a spiritual faculty, talent, or feeling due to disuse.
• Atrophied — Having undergone the process of atrophy; an organ, tissue, or muscle reduced in volume, weight, and functional capacity due to lack of activity, malnutrition, or neurological disease. Figuratively, it describes a spiritual faculty, talent, or feeling that has lost its original vigor, intensity, or structural efficiency due to lack of practice.
• Atrophic — Pertaining to atrophy, relating to atrophy, or exhibiting its characteristics; causing a structural and functional diminution of tissues. It is used in clinical terminology to define specific types of inflammatory, degenerative, or dermatological conditions characterized by marked thinning of membranes or organs.
• Atrophy — A pathological or physiological diminution of the volume, weight, and functional capacity of an organ, tissue, or component cells, caused by nutritional disorders, prolonged immobilization, denervation, or aging. Figuratively, it represents the weakening, regression, or loss of vigor and efficiency of a spiritual faculty, feeling, or intellectual capacity.
• Atrophoderma — A chronic dermatological condition characterized by the atrophy, thinning, and loss of elasticity of the skin, resulting in a depressed, flaccid, or wrinkled appearance of the affected areas. This structural process destroys collagen and elastin within the dermis, often associated with autoimmune diseases, local vascular disorders, or idiopathic premature aging.
• Atropous — Exhibiting the characteristics of an atropous (or orthotropous) ovule; a rectilinear and structurally inverted type of plant ovule, in which the micropyle, chalaza, and hilum are arranged along the same vertical line, continuing the direction of the funiculus. It represents the simplest and most primitive structural form of organization of the female reproductive apparatus found in certain gymnosperm and angiosperm plant families.
• Atropa — A genus of perennial herbaceous plants in the family Solanaceae, the most famous being Atropa belladonna (deadly nightshade). Species within this genus have a complex biological structure and are highly toxic, containing a large amount of tropane alkaloids (atropine, scopolamine) with major parasympatholytic effects, utilized in the structural pharmaceutical industry and medicine.
• Atropine — A toxic alkaloid extracted from deadly nightshade (Atropa belladonna) and other plants of the Solanaceae family, used in medicine as a parasympatholytic agent; it acts structurally by blocking acetylcholine muscarinic receptors, causing effects such as pupil dilation (mydriasis), reduction of glandular secretions, and acceleration of the heart rate. It represents an essential antidote in poisonings with organophosphorus pesticides or nerve gases.