prop root

An adventitious root that arises from the stem, penetrates the soil, and helps support the stem, as in corn. Also called brace root.

A root that acts as a prop or support. Prop roots originate from stems but ultimately penetrate the soil, serving both as anchors and as food gatherers. Corn and many tropical plants produce prop roots.

The noun has one meaning:

Meaning #1: a root that grows from and supports the stem above the ground in plants such as mangroves