General synonyms:
* Join: To bring together or link.
* Link: To join or connect.
* Attach: To fasten or connect.
* Couple: To join together.
* Unite: To bring together into one.
* Combine: To join together into a single whole.
* Associate: To connect in thought or feeling.
* Relate: To show or establish a connection between.
* Interconnect: To connect or link together.
Synonyms for specific types of connection:
* Network: To connect with others in a social or professional context.
* Communicate: To connect by means of words, signals, etc.
* Interface: To connect two systems or devices.
* Integrate: To connect or blend into a whole.
More specific synonyms:
* Bind: To tie or fasten together.
* Sew: To join together with thread.
* Weld: To join together by melting and fusing.
* Fuse: To melt and join together.
* Conjoin: To join or unite together.
* Coalesce: To come together and form one mass.
* Intertwine: To twist or weave together.
* Connect the dots: To make sense of something by connecting the different pieces.
The best synonym will depend on the specific situation and the type of connection being made.