1. not simple or easy; requiring significant effort, thought, or skill to understand or solve
Usage: often used in academic or technical contexts
2. important or significant; not minor or insignificant

Examples

• The math problem proved to be nontrivial and took hours to solve.
• Finding a cure for the disease is a nontrivial challenge.
• The software bug caused nontrivial delays in the project.
• She made a nontrivial contribution to the research.
• The cost of repairs will be nontrivial.
• This is a nontrivial decision that requires careful consideration.
• The algorithm handles nontrivial cases efficiently.