This interpretation is from the Pokemon Wiki:
Zeraora is a combination of the words zap, eradicate and tora, which means tiger in Japanese.
However this guy from GameFAQs interprets the name as something to do with 'zero'. It's certainly up for interpretation, but remember that Zeraora has the same name in Japanese, so all interpretations would need to work in Japanese too. This invalidates the possibility that the name comes from 'eradicate'.
I also couldn't help but see a parallel between Zeraora and Zekrom, who is also Electric-type. However, Ken Sugimori states that the 'ze' part of Zekrom's name is merely used to contrast the weaker sound 're' sound in 'Reshiram'. Knowing this, it may be possible that a 'z' sound was used to make Zeraora sound stronger. The 'z' sound also has an onomatopoeic resemblance to electricity.
Feel free to mention your interpretations and I'll add them to the answer.
Hope I helped. :)
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