From the Latin entente, meaning “agreeable occupation for the mind,” entertainment refers to activities that provide pleasure, diversion, or amusement. Often, entertainment is seen as frivolous or lighthearted, although it may also have a more serious purpose such as in ceremonies, religious festivals, or satire.
Entertaiment also hits on the points that our minds were evolved to react deeply to such as murders, social backstabbing and other themes in the human world we live in. It can stimulate the brain to realease seratonin and dopamine, which is a good thing considering our minds were shaped by evolution for a reason.
You might see entertainment abbreviated as entmt on a flier or in industry news publications, but it is generally not used in general writing.