1. The main stem or trunk of a tree or woody plant, especially the persistent base from which branches grow.
Usage: botanical; formal
2. In botany, the woody base of a perennial plant that persists from year to year.
Usage: botanical; technical

Examples

• The caudex of the ancient oak had grown thick and gnarled over centuries.
• Botanists examined the caudex to determine the age of the shrub.
• The plant's caudex remained alive underground even after the above-ground portions died back.
• A thick caudex supports the weight of the tree's extensive canopy.
• The caudex of perennial plants allows them to regrow each season.