Epic. That's the word for writers today.
Ever since Fellowship of the Ring burst out (albeit unassumingly) on bookstore shelves have a century ago, the genre of epic fantasy has been revolutionized. No longer are tales of elves and goblins confined to the parables told at the bedside. Instead, modern, adult fantasy (please, don't get any ideas) has blossomed and children's tales have yielded the stage.
Today, fantasy is widespread. You could say ubiquitous, for the shelves are full of understated, pulp fantasy. Examples include, to a certain extent, game-to-book adaptations and some larger series. However, epic fantasy, or High Fantasy, is different. It chronicles the events that shake empires, that move worlds, all against the background of fantastic creatures and strange magic. Fantasy is not fantasy if there is no magic or creatures. The time period does not matter, indeed, some epics have chronologies that span millions of years. Throughout these storyarcs, the stories of its characters, preferably not flat or one-dimensional ones, fill the pages. Epic fantasy is preferably human (as in, it deals with interpersonal relationships between characters), but set against the backgrounds of fabricated histories. Epic fantasy is also characteristically long and drawn-out.
Some examples of epic fantasy: Steven Erikson's Malazan Book of the Fallen series, Robert Jordan's Wheel of Time series, George RR Martin's A Sword of Ice and Fire series, Goodkind's Sword of Truth series, perhaps some of Donaldson's, Edding's, and Brook's works as well.