Etymology tree Proto-Indo-European *ḱe? Proto-Indo-European *ḱóm Proto-Italic *kom Proto-Italic *kom- Latin con- Proto-Indo-European *ḱers- Proto-Indo-European *-éti Proto-Indo-European *ḱr̥séti Proto-Italic *korzō Latin currō Latin concurrobor. English concur Borrowed from Latin concurro (“to run together, agree”).