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lubrication

(Encyclopedia)lubrication, introduction of a substance between the contact surfaces of moving parts to reduce friction and to dissipate heat. A lubricant may be oil, grease, graphite, or any substance—gas, liquid...

milk, food

(Encyclopedia)milk, liquid secreted by the mammary glands of female mammals as food for their young. The milk of the cow is most widely used by humans, but the milk of the mare, goat, ewe, buffalo, camel, ass, zebr...

ass

(Encyclopedia)ass, hoofed, herbivorous mammal of the genus Equus, closely related to the horse. It is distinguished from the horse by its small size, large head, long ears, and small hooves. There are three living ...

transmigration of souls

(Encyclopedia)transmigration of souls or metempsychosis mətĕmˌsəkōˈsĭs [key] [Gr.,=change of soul], a belief common to many cultures, in which the soul passes from one body to another, either human, animal, ...

cattle

(Encyclopedia)cattle, name for the ruminant mammals of the genus Bos, and particularly those of the domesticated species, Bos taurus and B. indica. The term oxen, broadly used, refers also to closely related animal...

rabbit

(Encyclopedia)rabbit, name for herbivorous mammals of the family Leporidae, which also includes the hare and the pika. Rabbits and hares have large front teeth, short tails, and large hind legs and feet adapted for...

Arthropoda

(Encyclopedia)Arthropoda ärthrŏpˈədə [key] [Gr.,=jointed feet], largest and most diverse animal phylum. The arthropods include crustaceans, insects, centipedes, millipedes, spiders, scorpions, and the extinct ...

first aid

(Encyclopedia)first aid, immediate and temporary treatment of a victim of sudden illness or injury while awaiting the arrival of medical aid. Proper early measures may be instrumental in saving life and ensuring a ...

antibiotic

(Encyclopedia)antibiotic, any of a variety of substances, usually obtained from microorganisms, that inhibit the growth of or destroy certain other microorganisms. Although for centuries preparations derived from ...

ectoderm

(Encyclopedia)ectoderm, layer of cells that covers the surface of an animal embryo after the process of gastrulation has occurred. This outer layer, together with the endoderm, or inner layer, is present in all ear...