Branch

• branch [countable]
• 1

  of a tree

  a part of a tree that grows out from thetrunk (=main stem) and that has leaves, fruit, or smaller branches growing from it [↪ limb]:
• After the storm, the ground was littered with twigs and branches.
• The topmost branches were full of birds.
• 2

  of a business/shop/company etc

  a local business, shop etc that is part of a larger business etc:
• The bank has branches all over the country.
• a branch office in Boston
• She now works in our Denver branch.
• Where's their nearest branch?
• They're planning to open a branch in St. Louis next year.
• Have you met our branch manager, Mr. Carlson?
• 3

  of government

  a part of a government or other organization that deals with one particular part of its work [↪ department]:
• All branches of government are having to cut costs.
• the executive/judicial/legislative branch (=the three main parts of the US government)
• 4

  of a subject

  one part of a large subject of study or knowledge [↪ field]
• a branch of mathematics/physics/biology etc
• 5

  of a family

  a group of members of a family who all have the sameancestors [↪ side]:
• the wealthy South American branch of the family
• 6

  of a river/road etc

  a smaller less important part of a river, road, or railway that leads away from the larger more important part of it:
• The rail company may have to close the branch line to Uckfield.
• WORD FOCUS: tree 
  parts of a tree: trunk, branch, leaf, blossom, roots, bark, twig
  a large area of trees: forest, rainforest, jungle
  a small area of trees: wood/woods, thicket British English, copseBritish English
  types of tree: evergreen, deciduous, conifer, fruit tree, hardwood tree
  wood from trees: timber, lumber, firewoodtree
  Definition from the Longman Dictionary of Contemporary English 
  Advanced Learner's Dictionary.