SLD

SLD can mean the following:

In Polish, SLD is short for Sojusz Lewicy Demokratycznej which is a Polish political party. In English, this party is called the Democratic Left Alliance.
In British politics, the party currently known as the Liberal Democrats used to be called the SLD, which stood for Social and Liberal Democrats
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SLD resolution (Selected Literal Definite clause resolution) is special kind of resolution that applies only to Horn clauses and which provides the execution mechanism for Prolog.
Second-level domain, an Internet domain directly beneath the top-level domain.
Symantec Livestate Delivery, software similar to RIS from Microsoft.
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