What is "bouser"

Usage examples of "bouser".

But for the smudge of oil left by his fingers, I could tell myself that none of it had happened, and get on with banging my typewriter keys, ordering mustard by the tub and jam by the barrel and currants by the sackload as the ordnance trucks trundled their deadly trains of long steel canisters across the concrete and the groundcrew hauled fuel bousers and the aircrew watched the maps being unrolled and the pointers pointed at the name of a town in Europe that would mean death for some of them.