The common name in the UK for molasses. Treacle is the dark sticky sweet goo that results from the boiled-down sugar cane juice left after the process of extracting (granulated) sugar. It's commonly used in baking or made in to candy (dark caramels or treacle taffy); some people like it on toast. I once met a fellow who swore by treacle and marmite sandwiches. I've never yet been brave enough to try one, so I'll reserve judgement on them for now. Treacle is available in a variety of grades based on colour. Darkest is unrefined dark treacle (blackstrap molasses), which is very rich in calcium, and they range up to a light tan treacle.