a-, an- +
(Greek: a prefix meaning: no, absence of, without, lack of, not)
These prefixes are normally used with elements of Greek origin, a- is used before consonants and an- is used before vowels.
It affects the meanings of hundreds of words.
There are too many words that use these prefix elements to list all of them on this site; however, there are significant examples listed in this and the other units where they exist.
anarthria
Loss of articulate speech.
anastral
Lacking an astrosphere.
anecdysis
The absence of molting or a prolonged intermolt period.
anechoic
Free from echoes; completely absorbing sound waves or radar signals.
anemia
1. A lack of red blood cells.
2. A condition in which a person's blood does not have enough red corpuscles.
anemotrophy
Lack of substances essential to the formation of blood, thereby resulting in hypoplastic anemia.
anencephaly
1. Congenital defective development of the brain, with absence of the bones of the cranial vault and absent or rudimentary cerebral and cerebellar hemispheres, brainstem, and basal ganglia.
2. Partial or total absence of the brain at birth.
anenterous
Lacking intestines.
anenzymia
Congenital absence of an enzyme.
anephric
Without kidneys.
anephrogenesis
Congenital absence of kidney tissue.
anergy
Lacking energy.
aneroid
Without fluid.
anerythroplasia
A condition in which there is no formation of red blood cells.
anesthesia
1. A total or partial loss of the sense of pain, temperature, touch, etc.
2. A partial or complete loss of sensation, with or without the loss of consciousness; as a result of disease, injury, or the administration of an anesthetic agent; usually by injection or inhalation.
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