At a loss of time. Usually happens when either dumb, drunk, high, well-sexed, post-comatose, or cerebrally traumatized. Usually leads to negativeconsequences...
I was boffing my secretary so hard that I became temporally disoriented and missed my 3 o'clock.
Me and Rob got spliffed and, in a classic example of temporal disorientation, forgot to meet up w/ my hook up for another bag.
Disoriented is the American English version of it's more clunky sounding British English counterpart: disorientated. They both mean to be confused, lost, or to have lost ones bearings or sense of direction.
Disorientated is the British spelling/pronunciation (originally from a French word) of the US slurred and lazy variant disoriented. Meaning: Confused. To lose one's sense of direction.
It appears in all English dictionaries (as opposed to US-English) and the word has been in use since (at least) circa 1704.
Whilst walking around the numerous corridors of his new college, George became disorientated and couldn't find his way back out.