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adj. Related or tending to abstractionism, particularly art.

n. Someone who supports or creates abstract art.

n. An idealist.

n. One who occupies himself with abstractions; an idealist; a dreamer.

n. a painter of abstract pictures

adj. not representing or imitating external reality or the objects of nature

"“abstractionist” view (following the terminology of Van Inwagen 1986), or “ersatz” view (in the terminology of Lewis 1986) is prima facie committed only to representations, as a modal fictionalist must it seems also be, but the abstractionist is a realist about possible worlds, and thus has prima facie a more straightforward approach than the fictionalist's."

nonrepresentational   

idealist