Mine was OS X dictionary IIRC, but here's dictionary.com:
adjective, Also, epical
1.
noting or pertaining to a long poetic composition, usually centered upon a hero, in which a series of great achievements or events is narrated in elevated style:
Homer'sIliad is an epic poem.
2.
resembling or suggesting such poetry:
an epic novel on the founding of the country.
3.
heroic; majestic; impressively great:
the epic events of the war.
4.
of unusually great size or extent:
a crime wave of epic proportions.
5.
Slang. spectacular; very impressive; awesome:
Their burgers and fries are epic!
So if (4) is what you mean, it's not exactly the first definition for the adjective either.
adjective, Also, epical 1. noting or pertaining to a long poetic composition, usually centered upon a hero, in which a series of great achievements or events is narrated in elevated style: Homer'sIliad is an epic poem. 2. resembling or suggesting such poetry: an epic novel on the founding of the country. 3. heroic; majestic; impressively great: the epic events of the war. 4. of unusually great size or extent: a crime wave of epic proportions. 5. Slang. spectacular; very impressive; awesome: Their burgers and fries are epic!
So if (4) is what you mean, it's not exactly the first definition for the adjective either.