In this article we will conduct a review (influenced by critical historiography and critical discourse analysis) of the circulation of some terms characteristic of political-linguistic discourse and linguistic planning in the context of the discourse about language developed in Galiza throughout the last thirty years. We focus our attention especially on the terms “diglossia”, “linguistic normalisation” and “linguistic conflict”, which have come to occupy a central position in the Galician context, marked on the plane of identitary politics by the confrontation between two conflicting nationalist ideologies —identification with a nation with State (Spanish nationalism) and identification with a nation without State (Galician nationalism)—, and on the plane of language planning by (a) the conflict generated by the process of standardisation of one normative model for the Galician-Portuguese of Galiza, and (b) the critique generated by Galician linguistic nationalism of the language planning measures implemented by the autonomous government of Galiza. All of this must be understood against a general background shaped by the advanced linguistic substitution suffered by the Galician-Portuguese varieties spoken in Galiza in favour of Spanish