General:
* Significant Other: This is the most common meaning, referring to a romantic partner.
* State of: Often used in phrases like "State of the Art" or "State of the Union".
* Standard Operating: Used in phrases like "Standard Operating Procedure".
Technical:
* Sulfur Oxide: A chemical compound.
* Sound Only: Used in video conferencing or audio-only communication.
* Serial Output: A data transmission method.
Other:
* Second Order: Used in mathematics and statistics.
* Shipping Origin: Used in logistics and shipping.
To figure out the correct meaning of "SO", you need to consider the context of the sentence or phrase it's used in.