[EN] Researchers have traditionally established a link between synonymy and variation. This connection has been used to analyse phraseological units and their relationships within the language. Numerous extensive studies have been carried out on variation in phraseological units and their differentiation from synonymy. Recently, however, synonymy has begun to be understood as formal variation of the same semantic content within a functional language, either as free alternation (restricted view) or free alternation with complementary distribution (broad view). Thus, the aim of this work is to review the existing positions regarding the relationship between variation and synonymy in idioms as seen in various studies on this type of phraseological unit, before finally offering our own particular perspective on the question

Este trabajo se inserta en las líneas de investigación “Relaciones semánticas y niveles lingüísticos” y “Fraseología y Fraseografía”, que estamos desarrollando en el marco del Grupo de Investigación de Excelencia “Semaínein” (HUM 147), financiado por el Plan Andaluz de Investigación de la Junta de Andalucía en sus sucesivas convocatorias.