noun
- the boss of a shield, especially the round projection at the center
- a rounded knob or projection
- the beak of a bivalve shell
Usage: historical; military
Usage: technical
Usage: biology
Examples
- The ancient warrior’s shield featured an iron umbo at its center.
- Roman shields were reinforced with a metal umbo for both protection and offense.
- The archaeologist identified the shield fragment by its distinctive umbo.
- The door handle had a decorative umbo that caught the light.
- Marine biologists examine the umbo to determine the age of the clam.
- The umbo of the mussel shell showed signs of wear from the rocky substrate.