ETYM French bastion (cf. Italian bastione), from Late Lat. bastire to build (cf. French bâtir, Italian bastire), perh. from the idea of support for a weight, and akin to Greek bastazein to lift, carry, and to Eng. baston, baton.
1. A group that defends a principle.
2. A stronghold into which people could go for shelter during a battle; SYN. citadel.
3. Projecting part of a rampart or other fortification.
Tower at the corner of a fortification.
Earthwork projecting outward from fortification.
Strength; resistance to the elements or to hardship.
ETYM Latin immunitas, from immunis free from a public service; pref. im- not + munis complaisant, obliging, cf. munus service, duty: cf. French immunité. Related to Common, Mean.
The protection that organisms have against foreign microorganisms, such as bacteria and viruses, and against cancerous cells (see cancer). The cells that provide this protection are called white blood cells, or leukocytes, and make up the immune system. They include neutrophils and macrophages, which can engulf invading organisms and other unwanted material, and natural killer cells that destroy cells infected by viruses and cancerous cells. Some of the most important immune cells are the B cells and T cells. Immune cells coordinate their activities by means of chemical messengers or lymphokines, including the antiviral messenger interferon. The lymph nodes play a major role in organizing the immune response.
Immunity is also provided by a range of physical barriers such as the skin, tear fluid, acid in the stomach, and mucus in the airways. AIDS is one of many viral diseases in which the immune system is affected.
Immunity has been studied mostly in higher vertebrates, especially rodents, domestic animals, and primates.
The quality of being unaffected by something.
ETYM French résistance, Late Lat. resistentia, from resistens, -entis, p. pr. Related to Resist.
The ability to impede (resist) the flow of electric current. With the exception of superconductors, all substances have a greater or lesser degree of resistance. Substances with very low resistance, such as metals, conduct electricity well and are called conductors. Substances with very high resistance, such as glass and rubber, conduct electricity poorly and are called nonconductors or insulators.
In physics, that property of a substance that restricts the flow of electricity through it, associated with the conversion of electrical energy to heat; also the magnitude of this property. Resistance depends on many factors, such as the nature of the material, its temperature, dimensions, and thermal properties; degree of impurity; the nature and state of illumination of the surface; and the frequency and magnitude of the current. The si unit of resistance is the ohm.
1. (Psychiatry) An unwillingness to bring repressed feelings into conscious awareness.
2. Any mechanical force that tends to retard or oppose motion.
3. Group action in opposition to those in power.
4. The action of opposing something that one disapproves or disagrees with; SYN. opposition.
5. The condition in which an organism can resist disease.
6. The military action of resisting the enemy's advance.