This article discusses problems arising due to lack ofscholarly accord regarding the definition of the term idiom. Following a critical review of several of these definitions, a new category of idiom, which I have termed vivid phrasal (VP) idiom, is suggested. The subclassification of VP idioms along a conceptual Lexical-Image Continuum is then pre- sented. I suggest tliat while there still exist various means of categorizing idioms, agree- ment among idiomatologists regarding the definition of idiom can be reached and that, even more importantly, a common research agenda for second language acquisition re- searchers and language teachers is possible. Using empirical evidence, markedness fac- tors, andimplicationaluniversalsforVPidioms, Imakerecommendationsforfutureidiom research. The article concludes with a discussion of the advantages of a common research agendafor the development ofstrategies to assure second andforeign language learners' idiomatic competence.