The term dyslexia is best defined as?

Dyslexia is a specific learning disability that affects reading and related language-based processing skills. It is characterized by difficulty with accurate and fluent word recognition and poor spelling and decoding abilities. These difficulties typically result from a deficit in the phonological component of language that is often unexpected in relation to other cognitive abilities and the provision of effective classroom instruction. Secondary consequences may include problems in reading comprehension and reduced reading experience that can impede vocabulary growth and background knowledge.