the philosophy or doctrines of Plato or his followers.
2.
a Platonic doctrine or saying.
3.
the belief that physical objects are impermanent representations of unchanging Ideas, and that the Ideas alone give true knowledge as they are known by the mind.
4.
(sometimes lowercase) the doctrine or practice of platonic love.
Origin
1560-70; < Neo-LatinPlatōnismus. See Platonic, -ism
Related forms
Platonist, noun, adjective
anti-Platonism, noun
anti-Platonist, noun, adjective
British Dictionary definitions for Platonism
Platonism
/ˈpleɪtəˌnɪzəm/
noun
1.
the teachings of Plato and his followers, esp the philosophical theory that the meanings of general words are real existing abstract entities (Forms) and that particular objects have properties in common by virtue of their relationship with these Forms Compare nominalism, conceptualism, intuitionism
2.
the realist doctrine that mathematical entities have real existence and that mathematical truth is independent of human thought
The philosophy of Plato, or an approach to philosophy resembling his. For example, someone who asserts that numbers exist independently of the things they number could be called a Platonist.