(1) Having the right side of the brain dominant.
(2) Of or relating to an individual having a consistent preference for use of the right side of the brain, hence, is usually associated with having a behavior dominated by emotion, creativity, and intuition, and being more adept at spatial and nonverbal concepts.
The human brain is separated by a longitudinal fissure creating two distinct cerebral hemispheres. The two sides of the brain resemble each other yet their functions are lateralized. Analytical, logical, and verbal functions, as well as skills for exact calculation and literal language are localized in the left hemisphere. Holistic, prosodic and intuitive functions, including skills for approximate calculations and contextual language are localized in the right hemisphere.
A right-brained person is described to be more inclined at using the right side of his brain. Hence, he is also described to being more emotional, creative and intuitive than being logical and analytical person.
However, lateralizations are not applicable in every case, and there is no such a person who is "left-brained only" or "right-brained only".