Synonyms for Abstract (same or very similar meaning)
WordNet sense 1 (a sketchy summary of the main points of an argument or theory):
outline, precis, synopsis
WordNet sense 2 (a concept or idea not associated with any specific instance):
abstraction
WordNet sense 3 (make off with belongings of others):
cabbage, filch, hook, lift, pilfer, pinch, purloin, swipe, nobble, snarf, sneak
WordNet sense 4 (not representing or imitating external reality or the objects of nature):
nonobjective, abstractionist, nonfigurative
WordNet sense 5 (of or relating to a style of art in which objects do not resemble those known in physical nature):
nonrepresentational
WordNet sense 6 (concerned with theories rather than their practical applications):
theoretical
WordNet sense 7 (constituting or existing only in the form of an idea or mental image or conception):
ideal
WordNet sense 8 (being or characterized by concepts or their formation):
conceptual
From the ODE community, based on WordNet
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