Dehydrache
The headache caused by dehydration from strenuous physical activity, binge drinking, lack of hydration in general, or a combination of all three.
Dude 1: Damn dude, I'm thirsty as hell and got a gnarly headache right now
Dude 2: Sounds like a dehydrache, drink some water man.
Dude 2: Sounds like a dehydrache, drink some water man.