Go on the briny is a phrase that refers to sailing on the ocean. It is derived from the phrase 'on the briney deep, ' which was popularized by the poem The Rime of the Ancient Mariner by Samuel Taylor Coleridge. The crossword solution for this phrase is SAIL, which is a four-letter word. Sailing is an activity that involves navigating a boat or ship across a body of water, usually with the use of sails and other navigational tools.