Entertaiment means enjoyable leisure activity, especially a diversion or amusement. The power of entertainment is demonstrated by the way a story, such as Scheherazade in the professional storytelling tradition, can inspire retellings in multiple different mediums: composers like Rimsky-Korsakov and Ravel used the tale in their orchestral works; filmmaker Pasolini made a film adaptation; and game designers have created innovative video games based on the story.
You may occasionally see the word abbreviated entmt on fliers or in industry news publications where space is limited. However, entmt is not common for general use. Other similar words that you might find useful are: edification, enjoyment, fun.