There's always more that can be said, but the part of the AskHistorians FAQ about Shakespeare features a really good answer by /u/texpeare to a similar question: Shakespeare is credited for inventing many common words we use today. If he was the first one to use them -with no definitions or explanations for what they meant in the text - how did the common folk derive their meaning and use them so often that they're still a part of our vernacular today? - hope that helps!