libra-, liber-, libri- +

The mechanisms which the body uses to keep its fluids close to neutral pH (that is, neither basic nor acidic) so the body can function as it should in a normal way.

1. A situation in which a body or object remains reasonably steady in a particular position while resting on a base that is narrow or small relative to its other dimensions.

For human beings, this most commonly involves remaining upright and steady on the feet: "He lost his balance on the icy side walk and broke his wrist as he fell down."
2. A condition in which two opposing forces or factors are of equal strength or importance so that they effectively cancel each other out and maintain stability.
3. To achieve or to maintain, or to cause someone or something to achieve or to maintain, a position of steadiness while resting on a narrow base.
4. An instrument used in laboratories and pharmacies to measure the mass or weight of a body.

A balance functions by measuring the force of gravity that the earth exerts on an object; such as, its weight.

Since the mass of an object is directly proportional to its weight, a balance can also be used to measure mass.

5. In medicine, a biological system which lets us know where our bodies where ever we are and to keep a desired physical position.

Normal balance depends on information from the inner ear, other senses; such as sight and touch, and muscle movements.

A person's sense of balance is specifically regulated by a complex interaction between the following parts of the nervous system:

• The inner ears, the labyrinth, monitor the directions of motions; such as, turning or forward-backward, side-to-side, and up-and-down motions.
• The eyes observe where the body is in space; that is, upside down, right side up, etc., and also the various directions of motion.
• Skin pressure receptors; such as, those located in the feet and seat sense what part of the body is down and when it is touching the ground.
• Muscle and joint sensory receptors report what parts of the body are moving.
• The central nervous system (including the brain and spinal cord) processes all the pieces of information from the four other systems to make some kind of functional sense our of the various bodily messages.

7. Etymology: "an apparatus for weighing", from Old French, (12th century) "balance, scales for weighing"; also in the figurative sense; from Middle Latin bilancia, from Late Latin bilanx, bilancem; from Latin (libra) bilanx, "(scale) having two pans".

1. Well weighed or considered; carefully thought out; formed, carried out, etc. with careful consideration and full intention; done of set purpose; studied; not hasty or rash.
2. When referring to people: Characterized by deliberation; considering carefully; careful and slow in deciding; not hasty or rash.
3. Leisurely, slow, not hurried: in movement or moving agents.

Carefully weighed in the mind.

1. With careful consideration; not hastily or rashly; of set purpose.
2. Without haste, leisurely, slowly.

The quality of being deliberate, or of showing careful consideration; absence of haste in making a decision.

1. The action of deliberating, or weighing a thing in the mind; careful consideration with a view to making a decision.
2. The consideration and discussion of the reasons for and against a measure by a number of councillors (e.g. in a legislative assembly).
3. Absence of hurry; slowness in action or movement; leisureliness.

1. Absence or destruction of equilibrium; to throw out of balance.
2. A loss of equilibrium (balance between different forces or aspects) attributable to an unstable situation in which some forces outweigh others; a loss or lack of stability.

A nursing outcome from the Nursing Outcomes Classification, NOC, defined as a balance of electrolytes and non-electrolytes in the intracellular and extracellular compartments of the body.

The equilibrium or balance between the amounts of electrolytes in the body; such as, calcium, sodium, and potassium; all of which are essential for normal health and functioning.

An instrument for measuring electromagnetic forces by balancing them against gravity.

1. A micro-balance in which the sample weight is obtained automatically, based on the force produced by current in a coil in a magnetic field.
2. A weighing balance which uses forces produced by known currents to balance unknown currents and, so make unknown weights come to within parts of a microgram.

1. That which is in a state of equilibrium; evenly balanced.
2. Evenly poised; balanced.

The state or condition of being equally balanced; equilibrium; equality of weight.

1. A physical state or sense of being able to maintain bodily balance.
2. The ability to maintain a mental state of calmness and composure.
3. A state or situation in which opposing forces or factors balance each and stability is attained.
4. In a physical sense: The condition of equal balance between opposing forces; that state of a material system in which the forces acting upon the system, or those that are taken into consideration, are so arranged that their resultant at every point is zero.
5. The state of equal balance between powers of any kind; equality of importance or effect among the various parts of any complex unity.
6. The condition of suspense or uncertainty produced by equality with the forces of opposing influences; neutrality of judgment or volition.
7. Etymology: from Latin æquilibrium, from æquus, "equal" + libra, "a balance, scale".