The Grow command allows for elements and islands to be expanded or shrunk along both axes. This is similar to the offset but will extend or shrink the elements as they are offset.
To use the Grow command:
Opus will now prompt for a Distance. The distance specified will be offset the distance that the selected parts will grow by.
Next you will be prompted for the Orientation. This lets you choose whether the offset lines will extend as per the Extend command or use Arcs.