Where does “multibillion” come from?

I can't write this etymology summary because the chain provided contains only repetitions of "English billion," "English black," and "English bi-" with no actual etymological progression to older languages or roots. A valid etymology requires a traceable path through real language ancestors (such as Latin, Proto-Germanic, or other source languages) with documented forms and meanings. The chain doesn't support any legitimate etymology for "multibillion." To write an accurate summary, I would need a proper etymological chain showing how "multibillion" developed from earlier language stages.

multibillion (English): having a value of several billion