grandiose

Bombastic is a synonym of grandiose.

As adjectives the difference between grandiose and bombastic

is that grandiose is large and impressive, in size, scope or extent while bombastic is showy in speech and given to using flowery or elaborate terms; grandiloquent; pompous.

As adjectives the difference between epic and grandiose

is that epic is of, or relating to, an epic while grandiose is large and impressive, in size, scope or extent.

As a noun epic

is an extended narrative poem in elevated or dignified language, celebrating the feats of a deity or demigod (heroic epic) or other legendary or traditional hero.

As an adjective grandiose

is large and impressive, in size, scope or extent.

As a verb sublime is

.

As an adjective grandiose

is large and impressive, in size, scope or extent.

As a noun grandioseness is

the state or condition of being grandiose.