Gilds (more commonly spelled today as "guilds") were associations of men and women sharing common interests. There were various types of such associations. Some gilds were fraternities created for socio-religious purposes, which included conviviality, communal religious celebration, and charity (usually mutual support). Other gilds had a more businesslike purpose. Members of the same craft or trade came to organize themselves in the Late Middle Ages into gilds. On one hand this was a response to efforts of borough governments to control trade and craft practices: craftsmen needed to band together to protect their interests, but also for self-regulation, to satisfy government requirements for the setting and policing of standards. On the other it was a mechanism for established practitioners to suppress competition by restricting practice of a trade or craft to gild members. The two purposes intersected in the apprenticeship system, which ensured that young men interested in following a craft acquired the necessary skills and were inculcated with the values of the gild establishment, while at the same time restricting competition to qualified craftsmen, by requiring several years of apprenticeship before an individual could graduate to running his own business. The same two principles applied to merchants, whose gilds came into existence earlier than those of the crafts. Since the mercantile element of the community was prominent and influential, merchant gilds could be powerful institutions within a town, although this varied considerably from place to place.
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* Information Please Encyclopedia: "guilds or gilds"

This definition is in context to Medieval Town. See more contextual defintions for Gild.