1. Outside the norm; beyond the pale
2. Different, but not necessarily in a bad way
"That cat Ricky's been acting weird lately. He's on some other shit."
Relating to the inexplicable dieselness of of older men. This is usually on display in the gym when the burly gentleman in his 60s walks over to the flat bench, throws three 45 lbs. plates on each side (315 lbs. to those who can't add that fast), and proceeds to bang out 5 sets of 12 reps each with no warm-up. Other examples of this phenomenon are the inability to beat an old guy (particularly a father type) in a fair type regardless of your size compared to his and the seeming ability of old ass men to pick up and carry three times their weight.
Mitch's grandpa was in the gym today throwing up 420. Isn't dude like 70?
It's old man strong, kid.