To rename the labels in Dimensions for the ribbon view:
Open the window to relabel.
Press the red access icon in the top left corner and click on Language/Description.
Click on Load Current Window.
Click the edit button.
Find the label to rename and edit the text.
Click Save.
To rename the labels using the classic view
Open up the window to rename.
Click on Info.
Click on Language/Description.
Click Load Current Window.
Click on Edit.
Type in the new Name.
Click Save.