on what the Buddha taught
Dhātu is often translated as element.
Element seems to be a proper translation. However it can be seen in a limited way, as chemical element or organic substance, while when I say ‘there is an element of danger to it’ it is immediately understood differently. And there are those dhātū like the beautiful, lustful, aversive, harmful, etc. (f.i. AN6.111).
To avoid confusion I use aspect instead.
Dhātu (f.) aspect.