Fiacca

Italian orgin, made popular by the Calabrese.

Sluggishness
Tiredness
Laziness
Feeble
Dull
Half-Hearted
Unexciting
Unimaginative
Wishy-Washy
Uninspired

Or in more slang:

Cant be fucked
Cant be bothered
No energy

My fiacca's at an all time high with work today
I have fiacca with that assignment tomorrow
Remember that time me and you had fiacca for work?
If i didn't have fiacca i'd be rich by now
I have an unbelievable amount of fiacca for work tomorrow