Definition from Wiktionary, the free dictionary
- (intransitive, of an object) To join (to another object): to attach, or to be intended to attach or capable of attaching, to another object.
- I think this piece connects to that piece over there.
- (intransitive, of two objects) To join: to attach, or to be intended to attach or capable of attaching, to each other.
- Both roads have the same name, but they don't connect: they're on opposite sides of the river, and there's no bridge there.
- (transitive, of an object) To join (two other objects), or to join (one object) to (another object): to be a link between two objects, thereby attaching them to each other.
- The new railroad will connect the northern part of the state to the southern part.
- (transitive, of a person) To join (two other objects), or to join (one object) to (another object): to take one object and attach it to another.
- I connected the printer to the computer, but I couldn't get it work.
- To join an electrical or telephone line to a circuit or network.
- When the technician connects my house, I'll be able to access the internet.
- To associate.
- I didn't connect my lost jewelry to the news of an area cat burglar until the police contacted me.
- To make a travel connection; to switch from one means of transport to another as part of the same trip.
- I'm flying to London where I connect with a flight heading to Hungary.
Related terms 
to join two or more pieces
to join an electrical or telephone line