whereby

[tkacka15]

“And if this gap reaches a ‘tipping point’ whereby the views of England are either overruled by or overrule votes in Scotland, Wales and Northern Ireland, the constitutional implications may extend beyond the specific question of whether or not the UK remains in the EU.” [From The Guardian.]

Is "whereby" a relative adverb in the above sentence?

Thank you.

 

[probus]

I have no idea what a relative adverb is but I can tell you that in this context whereby means "by means of which."

 

[MikeNewYork]

Many dictionaries list it as a conjunction. However, a case could be made for it being a relative adverb.