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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]


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.

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References in periodicals archive ?
Whether the MPU issues and the ongoing debate over the adoption of a definition of digital goods will be resolved at December's Governing Board meeting remains to be seen.
Changes include revised definitions of disability, a return to lifetime benefits, higher monthly coverage amounts and more optional coverages.
By agreeing upon a uniform definition of what constitutes a criminal gang, what describes a person as a member/associate of a gang, and what unlawful acts comprise gang-involved crime, the law enforcement profession can begin the difficult, but not impossible, task of reversing the current menace that has engulfed many of America's young people and their communities.
Such a conclusion is undercut by Congress's express consideration and rejection of proposed changes to the definitions of non-audit services prohibited by the existing SEC rule.
This element of the definition is deceptively simple.
This new definition added a small number of conditions which would be considered AIDS-defining if they occurred in a person with a positive HIV test.
Second, these definitions clearly illustrate a behavioral process or systems approach to teamwork.
Conceptual and psychometric concerns about the 1992 AAMR definition of mental retardation.
This section of the definition stands as an example that the Health Security Act was intended as an overarching plan with the details to be fleshed out.
However, I have yet to see a definition or category devised by a federal or state agency that does not fit into the CDC categories.