A modern building is a structure that is built with cutting-edge techniques and materials to meet modern-day needs. There are several synonyms for modern building that capture different nuances of the phrase, such as contemporary, sleek, stylish, innovative, and avant-garde. These words suggest that the building is not just new or up-to-date, but also reflects the latest trends in design, technology, and functionality. Other related terms include futuristic, state-of-the-art, minimalist, and eco-friendly, all of which convey a sense of freshness, efficiency, and sustainability. Therefore, when choosing words to describe a modern building, it is important to consider the context and audience, and to select words that convey the desired message.