Adjective

(en adjective)

Of extraordinary might, power, size, etc.; of or relating to Hercules in size or strength.

* 1607 , Shakespeare, Antony and Cleopatra, i 3 :

But this is not the best:--look, pr'ythee, Charmian, / How this Herculean Roman does become / The carriage of his chafe.

* (rfdate) :

It was truly a Herculean effort. I never thought it was going to happen, but it did.

Requiring a huge amount of work; of extraordinary difficulty.

a Herculean''' labour'', ''a '''Herculean task

* 1748, Tobias George Smollett, The Adventures of Roderick Random

He replied in a dry manner, that I would find it a Herculean task to chastise everybody who should laugh at my expense;

* 2006 : Jeremy Clarkson, Top Gear , commenting on the Bugatti Veyron

The guys at Volkswagen have a Herculean task.

Adjective

(en adjective)

In the manner of a monument.

Large, grand and imposing. Fitting to be a monument to someone or something.

Taking a great amount of time and effort to complete.

*{{quote-magazine, year=2012, month=March-April

, author= , title=Well-connected Brains , volume=100, issue=2, page=171 , magazine=(American Scientist) citation , passage=Creating a complete map of the human connectome would therefore be a monumental milestone but not the end of the journey to understanding how our brains work.}}

"a monumental task"