The word 'haired' describes someone or something that has hair. For example, you can say 'a brown-haired girl' to describe a girl with brown hair.
You pronounce 'haired' like this: 'haird'. It rhymes with 'bared'.
The word 'haired' comes from the word 'hair', which has roots in Old English. It has been used for a long time to describe people or animals based on their hair.