(US) A style of pleasantness, courtesy, cooperation, and helpfulness associated with Minnesota culture; a form of Northern Plains charm.

(US) pleasant, courteous, cooperative, and helpful (as associated with Minnesota culture)

Pleasing to the eye; attractive.

plural of nice guy

(emergency medicine) Initialism of biological, nuclear / radiological, incendiary, chemical, and explosive agents, used to remember the types of hazmat emergencies.

(simile) Perfectly all right; fine. / (simile) Neat, tidy, in order.

(simile, colloquial) Very nice.

(US) To be friendly or conciliatory towards another, often in the context of maintaining good relations or resolving a conflict with the other person.

(UK, colloquial) Good-natured, while also being rather unintelligent.

(astronomy) A scenario for the dynamical evolution of the Solar System, proposing the migration of the giant planets from an initial compact configuration into their present positions, long after the dissipation of the initial protoplanetary gas disk.