Meaning of word 'ideologie' that Antoine Destutt de Tracy coined in 1790s to refer to new 'science of ideas' had very short-term currency. By 1830s, three other senses of term had superseded his explicit use designating empirical science of ideas - 1) denoting affliation to form of secular liberal republicanism; 2) perjorative connotation implying intellectual and practical sterility as well as dangerous radicalsim; 3) indicating political doctrine.
Among meanings attached to ideology are: political belief system action-oriented set of political ideas ideas of ruling class world view of particular social class or group political ideas embodying/articulating class or social interests ideas propogating false consciousness amongst exploited/oppressed ideas situating individual within social context and generating sense
of collective belonging officially sanctioned set of ideas used to legitimize political system/regime all-embracing political doctrine claiming monopoly on truth asbtract and highly systematic set of political ideas
If memory serves, Terry Eagleton identifies sixteen meanings/uses of word ideology in his appropriately entitled book _Ideology_. Michael Hoover