1. things that are not known or identified
Usage: plural form
2. people who are not famous or recognized
Usage: plural form
3. variables or quantities whose values are not determined
Usage: mathematics; plural form

Examples

• The equation has two unknowns that need to be solved.
• There are still many unknowns about the disease.
• The casting director decided to hire unknowns for the lead roles.
• Scientists are working to reduce the unknowns in climate modeling.
• The movie featured several unknowns who later became famous.
• We must account for the unknowns in our risk assessment.
• The algebra problem contains three unknowns: x, y, and z.