The Universal is terms, similitudes, and humors received by man and nation and prevailing either by conquest or by the authority of genius.
A Universal is the idea that there is some kind of property like squareness or blueness which is instantiated in a particular, for example blueness is instantiated in the sky or in the ocean, or squareness is instantiated in a box or a piece of paper.
The Universal is a notion that what occurs in a particular case may also occur elsewhere. It has to do with heuristic and analytic procedures, not existences.
A Universal is a technical notion in metaphysics meant to capture the intuition that a variety of things can all have the same feature or property. A bowling ball, a basketball, and a figure drawn on a blackboard can be round. There are a huge number of properties. Each (shared) property is a universal a 'one over many instances' whiteness over the many white things, roundness over the many round things. . ..
A Universal is such that if particulars are to have meaning, then there must be universals.
The Universal is not connected to the particular, but both are external and accidental to one another, as are the collected particularities . . . . And each thing is interconnected and interdependent with each other thing, so that each thing will contribute to the essential or necessary connection [of facts].
The Universal is such that, once reached, it ought to include within it the individuality with which we started: it should be a supreme Self which gives each self its identity.