Which word does NOT belong with the others? unimportant, trivial, insignificant, familiar

Given data

• Options: unimportant, trivial, insignificant, familiar.

Concept/Approach
Check for synonym groups and isolate the semantic outlier.

Step-by-step reasoning
Unimportant, trivial, and insignificant are near-synonyms meaning of little importance.Familiar means well known or well acquainted, which is unrelated to importance.

Verification/Alternative
Substitute test: a trivial matter equals an unimportant or insignificant matter; a familiar matter does not imply low importance.

Common pitfalls

• Confusing commonness with lack of importance; something familiar can still be very important.

Final Answer
familiar