1. lacking proper respect, politeness, or formality; abrupt or rude
2. without ceremony or formality; informal

Examples

• The security guard gave him an unceremonious shove toward the exit.
• She made an unceremonious departure, leaving without saying goodbye.
• The CEO’s unceremonious firing shocked the entire company.
• He dropped the package on the table in an unceremonious manner.
• The meeting came to an unceremonious end when the power went out.
• Her unceremonious dismissal of his ideas hurt his feelings.
• The old building met an unceremonious fate when it was demolished.