1. to sell more of something than is available or can be delivered
Usage: common in business and commerce
2. to promote or describe something in exaggerated terms; to make something seem better or more valuable than it actually is
Usage: common in marketing and advertising

Examples

• The airline oversold the flight and had to ask for volunteers to take a later departure.
• The company oversold its new product, promising features that weren't actually ready.
• Don't oversell yourself in the interview; let your qualifications speak for themselves.
• The marketing team tends to oversell the benefits of the software to potential clients.
• We oversold our inventory last quarter and couldn't fulfill all the orders on time.
• He oversold the movie to his friends, so they were disappointed when they watched it.