Word of the Day: 'Thalweg'

Beyond helping to define state borders and being used by geologists to trace the slope between two points, ‘thalweg’ is used by stream restorationists in determining the deepest part of a river or stream — and therefore the line of highest water velocity.
So I can easily imagine someone inventing a whole series of instructions based on proper approach to a stream’s thalweg. Or specialized casts and mends designed to plumb the depths of the thalweg. Or an ambitious writer describing how “the scaly beast headed straight for the thalweg.” Or a new fast-sinking fly line series called “Thalweg Exstream.” Oops, I hope no fly line marketers are reading this.