Did a search on Google and found
Two-Year-Olds Readily Learn Multiple Labels for the Same Basic-Level Category
which is a perfect find!
(nameless superordinate is a descriptive phrase that came out of my fingers as I was typing a sentence where I was coming up with a possible generic form of hypernym but without a name – and not limiting to words either)
On to Google scholar citations of it! Good to be back to words again.