We translated the ABC adherence taxonomy (i.e., seven terms and their corresponding definitions) published by Vrijens et al. (2012) into French (F) and German (G) without changing the original meaning with the aim to promote a standardised taxonomy for medication adherence to French- and German-speaking researchers and clinicians. A Delphi survey was performed. To generate round one, we identified French and German synonyms for the seven adherence terms through a literature search in Pubmed. Investigators translated the original English definitions into French and German. Panellists were members of ESPACOMP - the International Society for Patient Medication Adherence; experts suggested by ESPACOMP members and first authors of medication adherence publications in French and German. Google forms were used to create online questionnaires. Delphi rounds were performed until consensus was reached. The consensus was defined according to the acceptance rate as moderate consensus (50-75%), consensus (>75-95%), and strong consensus (>95%). The literature search resulted in four to six (F) and four to seven (G) items per English term. Delphi rounds were launched between November 2016 and April 2018. Three rounds sufficed to reach consensus on all terms and definitions from 26 French-speaking and 25 German-speaking panellists. Preferred terms for medication adherence are "adhésion médicamenteuse" (82%) in French and "Medikamentenadhärenz" (88%) in German. The use of a common terminology for medication adherence with translations in French and German will contribute to standardise the vocabulary, to harmonise research projects and ultimately ease comparison of study results among researchers and clinicians. This article is protected by copyright. All rights reserved.