A branch (UK /ÃËbrÃâÃÂntÃÆ/ or UK /ÃËbræntÃÆ/, US /ÃËbræntÃÆ/) or tree branch (sometimes referred to in botany as a ramus) is a woody structural member connected to but not part of the central trunk of a tree (or sometimes a shrub). Large branches are known as boughs and small branches are known as twigs. Due to a broad range of species of trees, branches and twigs can be seen in many different shapes and sizes.