|This page in a nutshell: If two or more subjects have the same name, split them into two separate articles. Don't put them all in the same article.|
The chimera is a mythological creature with body parts from many different animals. Chimera articles are articles which, in a similar manner, are built from bits of different subjects. Chimera articles are distinct from disambiguation pages because they do not simply try to point readers at the page they were looking for: instead, they try to write about all of them at once.
This is a bad idea. When an editor lands on an article, he should be able to trust that every part of it refers to the same subject. This means that the article can be browsed at random without excessive confusion. It helps editors for the same reason.
Chimera articles are similar to Frankenstein articles, but the distinction is that Frankenstein articles are accidental (created due to improper diligence when gathering material from sources), where chimera articles are deliberate (created out of the impression that similar but distinct subjects are okay being given the same article).
By far the best alternative is to split the subjects up into different pages, linked either by hatnotes or by a separate disambiguation page.