Dictionary of Ichthyology  

hurdy-gurdy = an apparatus turned by a crank, e.g. in fisheries used to haul in a trawl or longline. Also called gurdy or trawl-roller.
Hurdy-gurdy, showing attachment to a dory, with a trawl-roller at top right. National Marine Fisheries Service, Washington. Photograph by Brian W. Coad.

Canadian Museum of Nature