If mathematics, unlike entomology, is unreasonably effective, it should be possible to say with, at least some precision, what it means for a mathematical object, structure, or theory to be applied to an object, structure or theory that is resolutely not mathematical. If it is possible to say as much, I have not found a way in which to say it. Mathematics is about mathematics; and so far as the Great Beyond is concerned, while it is obvious that mathematics is often applied, it is anything but obvious how this is done.
Berlinski, D. (2015). Mathematics and its applications. In Mathematics, Substance and Surmise: Views on the Meaning and Ontology of Mathematics (pp. 101–131). Springer International Publishing. https://doi.org/10.1007/978-3-319-21473-3_6