Something lexical relates to the words of a language. Dys in front of it says that something is wrong. Dyslexia is a disorder that many people associate with difficulty in spelling words. It is much more than this.
Some people call dyslexia 'a specific learning difficulty'.
Dyslexia tends to run in families. Dyslexia continues throughout life. Dyslexia people may have creative, artistic, practical skills. They can develop strategies for their areas of difficulty. Dyspraxia can make things worse for some people with dyslexia.