An example of metaphor in popular science writing,
"…'diagnostic drift'… refers to a particular diagnosis coming untethered from its initial conceptual moorings, so that a category of illness once tightly tied to very specific behaviours is suddenly relevant to everyone and his aunt, with the result that the disorder in questions …becomes so watered down, so deeply diluted, that it almost ceases to have any medical meaning at all."
Lauren Slater (2018). The Drugs That Changed Our Minds. Simon & Schuster.
Read about metaphor in science
Read about examples of science metaphors
Many examples of science metaphors are listed in 'Creative comparisons: Making science familiar through language. An illustrative catalogue of figurative comparisons and analogies for science concepts'. Free Download.
These may be seen as examples of 'extended metaphor' as forst the same imagery is referred to in a sequence of terms "untethered…moorings…tightly tied", and then two effectively* synonymous metaphors are used: "watered down…deeply diluted"
* diluted need not refer to aqueous solution (in science we may deal with a wide range of solvents, and indeed consider alloys in these terms) but in everyday life most commonly does.
