(chemistry) any theory in which all matter is composed of tiny discrete finite indivisible indestructible particles; "the ancient Greek philosophers Democritus and Epicurus held atomic theories of the universe"
(psychology) a theory that reduces all mental phenomena to simple elements (sensations and feelings) that form complex ideas by association
a behavioral convention or pattern characteristic of all members of a particular culture or of all human beings; "some form of religion seems to be a human universal"
(logic) a proposition that asserts something of all members of a class
(linguistics) a grammatical rule (or other linguistic feature) that is found in all languages
adapted to various purposes, sizes, forms, operations; "universal wrench", "universal chuck"; "universal screwdriver"
applicable to or common to all members of a group or set; "the play opened to universal acclaim"; "rap enjoys universal appeal among teenage boys"
any personal belief about how to live or how to deal with a situation; "self-indulgence was his only philosophy"; "my father's philosophy of child-rearing was to let mother do it"
the rational investigation of questions about existence and knowledge and ethics