What is a metaphorical collocation?

In research on collocations published in English we encounter, albeit rarely, the use of the notion “metaphorical collocations”. It is interesting to note that seldom if ever are metaphorical collocations defined in any way in these studies, suggesting that researchers find the term self-explanatory. However, seeing that metaphorical collocations are an exciting area of research that is yet to draw attention from the wider community of researchers, the aim of this paper is to analyze the current understanding of what a metaphorical collocation is by examining the theoretical foundations as well as studies, specifically those published in English (as the language of scientific research). Therefore, I examined publications in English (and German) for definitions of a metaphorical collocation, and I examined a number of studies on such collocations, or studies that refer to such collocations, in English. In view of theoretical considerations, I have found that metaphorical collocations indeed have an established definition, while in regard to research on such collocations, I have found that authors most often than not leave out the definition and actually label a wide range of multiword units as metaphorical collocations. I propose that for the sake of clarity and transparency in research on metaphorical collocations in English, researchers refer to and adhere to a definition of the notion. This is particularly important as metaphorical collocations are at the intersection of two quite complex linguistic phenomena: metaphors and collocations.