The word telephone has existed since the 17th century, but I think it was fair to call Alexander Graham Bell’s invention a telephone before every home had one.
What was a 17th century “telephone”. I doubt the definition in a 17th century dictionary would describe Bell’s design. Bell’s use wouldn’t have appeared in a dictionary until years after his invention or even general use of it. That’s how language works.
The dictionary would have to know about prior usage. If it is extremely limited in use, it would likely comment on this.
I take it from your response, as you seem knowledgeable on the subject, that this is the first actual use of mRNA to attempt vaccination in the general population.
I would expect, therefore, such a definition to NOT be in the dictionary, or if electronic, as it is, it could be there with such a distinction.
That this is not the case, probably is telling about the motivations of those providing the definition.