Cute Young Brunette Girl With A Red Flowers Tree Branch Posing In The Studio

A bough can also be called a limb or arm, and though these are arguably metaphors, both are widely accepted synonyms for bough.
A crotch is an area where a trunk splits into two or more boughs.
A twig is frequently referred to as a sprig as well, especially when it has been plucked. Other words for twig include branchlet, spray, and surcle, as well as the technical terms surculus and ramulus.
Branches found under larger branches can be called underbranches.