I’m new to working with revision control and sometimes get confused with merge terminology resulting in me merging the wrong way.
For future reference:
To transfer all the latest changes in the main trunk to the development branch, update to the main trunk. Then merge the branch and commit. The merge operation takes the trunk changes (which are in the current working directory from the update) and merges them INTO the chosen merge branch (switching to it in the process). The commit then goes to the branch.