1. very great in amount or degree; countless
2. not revealed or made known; kept secret

Examples

• The hurricane caused untold damage to the coastal towns.
• She inherited untold wealth from her grandmother.
• The war brought untold suffering to millions of people.
• There are untold stories waiting to be discovered in the archives.
• His untold secrets died with him.
• The ancient treasure holds untold value.
• Untold numbers of species live in the rainforest.