Merriam-Webster's Word of the Day for August 5, 2025 is contentious. Contentious is an adjective used to describe things likely to cause arguments or disagreement. It can also describe a person who is willing or prone to arguing. For instance, a contentious topic is best avoided at social gatherings. A contentious debate often involves a significant amount of back-and-forth discussion. The word can also apply to individuals, such as a contentious leader. The play "Amadeus" features the contentious relationship between Mozart and Salieri. Contentious implies a fondness for arguing that others may find tiresome. This contrasts with words like combative or belligerent, though similar in meaning. The word's origins trace back to the Latin word "contentiosus," meaning argumentative or quarrelsome.