Dictionary of Ichthyology  

boilie = a small, rounded, boiled artificial bait used by anglers in Europe. Usually egg is added to a paste bait giving it a hard skin that deters small fish. May be coloured and flavoured (e.g. spicy, fishmeal and sweet) and composed according to a variety of recipes (the best being secret of course). Effective against fish that have been caught many times, a function of the number of anglers, limited waters and available fish in Europe. A whole complex of recipes and equipment has grown up around this type of bait.

Wikimedia Commons: http://en.wikipedia.org/wiki/File:Boilies.jpg

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