A formulated definition of the term dyslexia is proposed in this paper in order to clarify the semantical confusion which exists among both specialists and the general public. Dyslexia is explained as a generic term for severe and puzzling reading disability, found to be both acute (where reading-age lags 25 percent or more below mental age) and chronic (resistant to treatment). Qualifiers are suggested to more precisely define the term. Specific dyslexia should be used where the intention is to indicate that there is no evidence of complications. Compund dyslexia will have primary (bearing on the origins of the problem) or secondary (resulting from the condition) complicating conditions. Etiological qualifiers should be congenital, suggesting genetic origins; psychoneurotic, suggesting origins in emotional reactions or distress; and constitutional, suggesting a disability arising from minimal brain damage, chemical imbalance, or constitutional trauma. A hierarchy of terms to describe lack of reading ability is as follows: sub-optimal, disabled, severely disabled, dyslexic, and alexic--a virtual nonreader. A distinction is made between dyslexia and illiteracy. The questionnaire sent to a number of professional educators asking their judgment on the definition of dyslexia is included. (MKM)