(redirected from Definitions)
Also found in: Dictionary, Thesaurus, Legal, Acronyms, Encyclopedia, Wikipedia.


a statement of the meaning of a word or phrase.
conceptual definition an identification of the personal knowledge or connotative meaning of a word. These meanings are often difficult to express; the meaning is “known” but not easily put into words.
operational definition a definition, method, or procedure used to measure or represent a concept or variable in a specific situation.
target definition the definition of a specific target that is identified on the intervention scheme of the omaha system.


In optics, the power of a lens to give a distinct image.
See also: resolving power.
[L. de-finio, pp. -finitus, to bound, fr. finis, limit]


Imaging The clearly delineated limit of a thing visible by the eye. Cf Resolution.


In optics, the power of a lens to give a distinct image.
See also: resolving power
[L. de-finio, pp. -finitus, to bound, fr. finis, limit]

definition (image),

n the property of projected images relating to their sharpness, distinctness, or clarity of outline. Penumbra width is a measure of definition. See also resolution.


establishment of a clear boundary, a clear line of demarcation.

clinical definition
an accurate description of the disease in terms of clinical signs and clinicopathological findings.
epidemiological definition
an accurate description of the disease in terms of its epidemiological parameters of when, where, why and how it has occurred.
genetic definition
an accurate description of a disease in terms of the familial relationships between affected animals.
radiographic definition
a sharp line of demarcation between radiographic densities. A gradual merging of densities creates blurring of the image.

Patient discussion about definition

Q. What is the Definition of Anemia? My doctor told me I have anemia, based on my latest blood tests. What is anemia?

A. In laymans terms it is low iron. Most women get it sometime in their lives due to menstration and other factors. You need to increase your iron intake. Lots of beets, beans, spinich, and lots of other foods can help.

Q. what is the definition of Autism? how would i know if one is autistic and the other one is not , or has only minor disorder ?

A. Autism is a brain development disorder that is characterized by impaired social interaction and communication, and restricted and repetitive behavior, all starting before a child is three years old. This set of signs distinguishes autism from milder autism spectrum disorders (ASD) such as pervasive developmental disorder not otherwise specified. Diagnosis should be made if suspected, by a specialits in child psychiatry or child developement.

Q. What is the definition of Autism?

A. Autism is defined by symptoms from each of the following three categories: qualitative impairment in social interaction, impairment in communication, and restricted repetitive and stereotyped patterns of behavior or interests.

By definition, the onset of autistic disorder is before the age of 3 years, although in some cases, it is not recognized until a child is much older.

You may read more here:

More discussions about definition
References in classic literature ?
Very commonplace, even ugly, that furniture of our early home might look if it were put up to auction; an improved taste in upholstery scorns it; and is not the striving after something better and better in our surroundings the grand characteristic that distinguishes man from the brute, or, to satisfy a scrupulous accuracy of definition, that distinguishes the British man from the foreign brute?
Do you happen to recall Herbert Spencer's definition of 'Life'?
That," he replied, "is all that any definition can do.
Remember," he warned, "my definition is fatal to metaphysics.
You have not yet picked out the flaw in my definition of philosophy.
But the objection is urged, 'that the honourable is the good,' and as every one equally desires the good, the point of the definition is contained in the words, 'the power of getting them.
Some lesser points of the dialogue may be noted, such as (1) the acute observation that Meno prefers the familiar definition, which is embellished with poetical language, to the better and truer one; or (2) the shrewd reflection, which may admit of an application to modern as well as to ancient teachers, that the Sophists having made large fortunes; this must surely be a criterion of their powers of teaching, for that no man could get a living by shoemaking who was not a good shoemaker; or (3) the remark conveyed, almost in a word, that the verbal sceptic is saved the labour of thought and enquiry (ouden dei to toiouto zeteseos).
Numerous instances could be given of characters derived from parts which must be considered of very trifling physiological importance, but which are universally admitted as highly serviceable in the definition of whole groups.
Nothing can be easier than to define a number of characters common to all birds; but in the case of crustaceans, such definition has hitherto been found impossible.
The principles of definition, the law of contradiction, the fallacy of arguing in a circle, the distinction between the essence and accidents of a thing or notion, between means and ends, between causes and conditions; also the division of the mind into the rational, concupiscent, and irascible elements, or of pleasures and desires into necessary and unnecessary-- these and other great forms of thought are all of them to be found in the Republic, and were probably first invented by Plato.
Professor Lloyd Morgan gives the following definition of "instinctive behaviour":
This definition is framed for the purposes of biology, and is in some respects unsuited to the needs of psychology.