Aphasia

n. impairment or loss of the ability to use and understand words

Aphasia (or aphemia) is a loss of the ability to produce and/or comprehend language, due to injury to brain areas specialized for these functions. It is not a result of deficits in sensory, intellect, or psychiatric functioning. (Brookshire, 1992; Goodglass 1993) It is also not muscle weakness or a cognitive disorder.
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Aphasia is condition characterized by either partial or total loss of the ability to communicate verbally or using written words. [more]Aphasia - Community and Resources

Noun
1. inability to use or understand language (spoken or written) because of a brain lesion
(hypernym) brain disorder, encephalopathy, brain disease
(hyponym) auditory aphasia, acoustic aphasia, word deafness

(n.)
Alt. of Aphasy