a Belonging to, or performed by, the intellect; mental; as, intellectual powers, activities, etc.
a Endowed with intellect; having the power of understanding; having capacity for the higher forms of knowledge or thought; characterized by intelligence or mental capacity; as, an intellectual person.
a Suitable for exercise | exercising the intellect; formed by, and existing for, the intellect alone; perceived by the intellect; as, intellectual employments.
a Relating to the understanding; treating of the mind; as, intellectual philosophy, sometimes called "mental" philosophy.