The kind of strong you get doing CrossFit workouts. Similar to "country strong." The men and women that do CrossFit Workouts rarely change in size, so the aren't huge, but they are extremely strong and have great endurance. Similar to country farm boys that do functional work daily. No abs can compare to the greatness of CrossFit abs. Total core workout.
Weightlifter: dude, you are not very big to be deadlifting all that weight, you need a weight belt.
CrossFitter: this is just my warm-up
Weightlifter: but you aren't a huge muscle head, like all my buds.
Crossfitter: no, I'm CrossFit strong!