English
intervenor
From intervene + -or.
A compound of intervene + -or
Proto-Indo-European *gʷem- ‘to come, to step’
Proto-Indo-European *gʷm̥yéti ‘to come’
Proto-Italic *gʷəniō ‘to come’
Latin veniō ‘come’
Latin interveniō ‘come between’
English intervene
Today it means
noun One who intervenes, especially in a legal sense.
Language periods are conventional ranges, not dates for this word.
Etymograph / intervenor