A more thorough explanation:

Lucrum cessans is a legal term that means "ceasing gain." It refers to damages that are awarded to compensate for a loss of anticipated profit in addition to an actual loss that has been realized. For example, if a business owner had a contract to sell 100 products for $10 each, but due to a breach of contract by the buyer, only 50 products were sold, the business owner may be entitled to damages for the lost profit on the remaining 50 products. This lost profit is known as lucrum cessans.