One who intervenes, especially relating to law.(noun)
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Use "intervenor" in a sentence
"The ballot measure also allowed members of the public to challenge unnecessary premium hikes, a so-called intervenor system similar to that in place in many public utility commissions."
"Because more than 250 residents or companies have been given so-called intervenor status in the case, the PSC says individual intervenors will be allowed to take part only through groups based on the county where they live."
"International Telephone & Telegraph Corp., which has been operated for the past couple of months by a government "intervenor" who is looking into the utility's costs and rates."