This paper focuses on the terminological problem of indiscriminate use of the terms contrastive and comparative or compared in analyzes made in interlanguageand/or intercultural studies of phraseological units, such as idioms or proverbs. The lack of consensus among scholars of phraseological units of Spanish language (and not only) on the use of these terms also leads to confusion of the methodologies used in research. The use of the terms equivalence, correspondence and concordance is analyzed and the methods for its establishment are reviewed as well.