so means: The amount of or degree that is expressed or understood in such a way. (in Merlin Dictionary)

What else does so mean?

It is evident to a large extent. (in Merlin Dictionary)

This is used to signal the beginning of a new topic or preface an observation. (in Merlin Dictionary)

The same applies to you. (in Merlin Dictionary)

Apparently; well, then. It is used to express surprise, disapproval or sarcasm. (in Merlin Dictionary)

Truth be told, it is true; certain. (in Merlin Dictionary)

It is used to intensify, particularly with verbs and verb phrases. (in Merlin Dictionary)

As indicated or stated in the following conditions: (in Merlin Dictionary)

Good order. (in Merlin Dictionary)

This is why we have. (in Merlin Dictionary)