Los padres de Juan son muy intolerantes y se enfadaron cuando les dijo que era gay.Juan's parents are very intolerant and they got angry when he told them he was gay.
This means that the noun can be masculine or feminine, depending on the gender of person it refers to (e.g. el doctor, la doctora).
No soporto a los intolerantes que creen que si no piensas como ellos estás mal.I cannot stand intolerant people who believe you are wrong if you don't think like them.