Clearly marked out or separated by a boundary or distinct dividing line.
From de- (distinctly) + marca (mark, boundary) from Medieval Latin. The Latin root 'marca' referred to border regions. The -ated suffix forms an adjective from the past participle of the verb.
Country borders and sports fields are demarcated lines, but your brain's right and left hemispheres also have demarcated regions—neuroscientists found that creative and logical thinking actually happen in different 'marked-off' zones.
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