Oxford Dictionary English sun lounge nounnoun BrE BrE//ˈsʌn laʊndʒ// ; NAmE NAmE//ˈsʌn laʊndʒ// (British English) (also sunroom North American English, British English) Add to my wordlistjump to other results a room with large windows, and often a glass roof, that lets in a lot of lightCheck pronunciation: sun lounge oxfordlearnersdictionaries.com