Using a cell phone during the exam is a nono.

She made a list of fashion nonos to avoid at the gala.

The nonobservant hiker missed the rare bird perched on the branch.

The committee discussed several nonobjectives that emerged during the brainstorming session.

Her nonobjective evaluation of the proposal raised concerns among the committee.

During the mission, a nonobjective emerged when the team discovered an unattended communications relay that needed securing.

Attendance at the workshop is nonobligatory, though signing up helps us plan materials.

The audit revealed numerous nonobservances of safety protocols that required immediate correction.

The nonobservance of safety protocols at the construction site led to several preventable accidents.

The nonobedient child ignored his mother's warnings and ran into the street.