Wiktionary
vb. 1 (context idiomatic intransitive English) To press a mound of something against something else. 2 (context idiomatic intransitive English) To make a mound to guard against something.
Usage examples of "bank up".
Joe waved, and then watched suspiciously as the sheriff walked along the Roybal ditch bank up to the borders of his beanfield.
By the sound of his voice I placed the mad colonel on the bank up above us&mdash.
A shady road, dotted here and there with dainty little cottages, runs by the bank up to the “.
He was riding the far bank up and down, between river and millrace, alone.
I put the pony at the bank up to the road, won the brief battle when he tried to turn for home, then kicked him to a canter along the path which led upstream into the hills.
He laid out stakes up the valley of the Sera to the cluster of stone houses at Rimagno, crossed the Sera River at a shallow ford and followed the contour of the bank up the steep gorge.
Terence and Cyril were already out of the boat and climbing the steep bank up to the bridge.