Also found in: Acronyms, Wikipedia.
1. Currently undergoing construction or repair work. The famous cathedral has been under construction to varying degrees since 1882. Sorry, the road here is under construction, so you'll have to go a different way.
2. Currently being designed or coded. Said of something distributed on or accessed via the Internet, especially a website. Our new homepage is under construction, but you can still buy merchandise from our online shop. By popular demand, I'm thrilled to announce that we will soon have a new app for smartphones! It is currently under construction and should be available this fall.
Fig. being built or repaired. We cannot travel on this road because it's under construction. Our new home has been under construction all summer. We hope to move in next month.