Hearing Impairment - HI:  "Hearing impairment" means an impairment in hearing in one or both ears, with or without amplification, whether permanent or fluctuating, that adversely affects a child's educational performance but that is not included under the definition of deafness in this section. (34 CFR 300.8(c)(5)

Deafness:  "Deafness" means a hearing impairment that is so severe that the child is impaired in processing linguistic information through hearing, with or without amplification, that adversely affects the child's educational performance. (34 CFR 300.8(c)(3))

Visual Impairment including Blindness - VI:  "Visual impairment including blindness" means an impairment in vision that, even with correction, adversely affects a child's educational performance. The term includes both partial sight and blindness.(34 CFR 300.8(c)(13)).

Deaf-blindness - DB:  "Deaf-blindness" means simultaneous hearing and visual impairments, the combination of which causes such severe communication and other developmental and educational needs that they cannot be accommodated in special education programs solely for children with deafness or children with blindness. (34 CFR 300.8(c)(2)).

Orthopedic Impairment - OI:  “Orthopedic impairment" means a severe orthopedic impairment that adversely affects a child's educational performance. The term includes impairments caused by congenital anomaly, impairments caused by disease (e.g., poliomyelitis, bone tuberculosis, etc.), and impairments from other causes (e.g., cerebral palsy, amputations, and fractures or burns that cause contractures). (34 CFR 300.8(c)(8))

Traumatic Brain Injury - TBI:  "Traumatic brain injury" means an acquired injury to the brain caused by an external physical force, resulting in total or partial functional disability or psychosocial impairment, or both, that adversely affects child's educational performance. Traumatic brain injury applies to open or closed head injuries resulting in impairments in one or more areas, such as cognition; language; memory; attention; reasoning; abstract thinking; judgment; problem-solving; sensory, perceptual, and motor abilities; psychosocial behavior; physical functions; information processing; and speech. Traumatic brain injury does not apply to brain injuries that are congenital or degenerative, or to brain injuries induced by birth trauma. (34 CFR 300.8(c)(12))

Intellectual Disability – ID:  "Intellectual disability" means the definition formerly known as "mental retardation" and means significantly subaverage general intellectual functioning, existing concurrently with significant deficits in adaptive behavior and manifested during the developmental period that adversely affects a child's educational performance. (34 CFR 300.8(c)(6)) ]

Emotional Disability - ED:  "Emotional disability" means a condition exhibiting one or more of the following characteristics over a long period of time and to a marked degree that adversely affects a child's educational performance: (34 CFR 300.8(c)(4))
1.  An inability to learn that cannot be explained by intellectual, sensory, or health factors;
2.  An inability to build or maintain satisfactory interpersonal relationships with peers and teachers;
3.  Inappropriate types of behavior or feelings under normal circumstances;
4.  A general pervasive mood of unhappiness or depression; or
5.  A tendency to develop physical symptoms or fears associated with personal or school problems.
Emotional disability includes schizophrenia. The term does not apply to children who are socially maladjusted, unless it is determined that they have an emotional disability as defined in this section.
 
Autism - AUT:  "Autism" means a developmental disability significantly affecting verbal and nonverbal communication and social interaction, generally evident before age three, that adversely affects a child's educational performance. Other characteristics often associated with autism are engagement in repetitive activities and stereotyped movements, resistance to environmental change or change in daily routines, and unusual responses to sensory experiences. Autism does not apply if a child's educational performance is adversely affected primarily because the child has an emotional disturbance. A child who manifests the characteristics of autism after age three could be identified as having autism if the criteria in this definition are satisfied. (34 CFR 300.8(c)(1))
 
Other Health Impairment - OHI:  "Other health impairment" means having limited strength, vitality or alertness, including a heightened alertness to environmental stimuli, that results in limited alertness with respect to the educational environment, that is due to chronic or acute health problems such as asthma, attention deficit disorder or attention deficit hyperactivity disorder, diabetes, epilepsy, a heart condition, hemophilia, lead poisoning, leukemia, nephritis, rheumatic fever, and sickle cell anemia and Tourette syndrome that adversely affects a child's educational performance. (34 CFR 300.8(c)(9))
 
Specific Learning Disability - SLD:  “Specific learning disability" means a disorder in one or more of the basic psychological processesinvolved in understanding or in using language, spoken or written, that may manifest itself in the imperfect ability to listen, think, speak, read, write, spell or to do mathematical calculations, including conditions such as perceptual disabilities, brain injury, minimal brain dysfunction, dyslexia, and developmental aphasia. Specific learning disability does not include learning problems that are primarily the result of visual, hearing, or motor disabilities; of  intellectual disabilities; of emotional disabilities; of environmental, cultural, or economic disadvantage. (§ 22.1-213 of the Code of Virginia; 34 CFR 300.8(c)(10))
 
Developmental Delay (ages 2-6) - DD:  "Developmental delay" means a disability affecting a child ages two by September 30 through six, inclusive: (34 CFR 300.8(b)
1.  Who is experiencing developmental delays, as measured by appropriate diagnostic instruments and procedures, in one or more of the following areas: physical development, cognitive development, communication development, social or emotional development, or adaptive development, or who has an established physical or mental condition that has a high probability of resulting in developmental delay;
2.  The delay(s) is not primarily a result of cultural factors, environmental or economic disadvantage, or limited English proficiency; and
3.  The presence of one or more documented characteristics of the delay has an adverse affect on educational performance and makes it necessary for the student to have specially designed instruction to access and make progress in the general educational activities for this age group.
 
Speech or Language Impairment - SLI:  "Speech or language impairment" means a communication disorder, such as disfluency (stuttering), impaired articulation, expressive or receptive language impairment, or voice impairment that adversely affects a child's educational performance. (34 CFR 300.8(c)(11))
 
Multiple Disabilities - MD:  "Multiple disabilities" means simultaneous impairments (such as intellectual disability with  blindness, intellectual disability with orthopedic impairment), the combination of which causes such severe educational needs that they cannot be accommodated in special education programs solely for one of the impairments. The term does not include deaf-blindness. (34 CFR 300.8(c)(7))