Intelligence is the act of interligare (to connect). In that sense AI is a degree of connectedness -enormously less than human intelligence indeed!
Intelligent systems connect a stimulus with a response… Now… the quality of that response defines the degree of the intelligence implied, and it relates to the complexity of the nervous or cybernetic system which manages the process.
Human intelligence is not a set factor -it is a huge variable, almost as huge as the difference in intelligence between some animals.
What we love about human intelligence is the possibility of becoming proactive, instead of reactive, but that is also a degree of connectedness.
A tool becomes intelligent when it is capable of generating a response to a certain stimulus -say a rat trap which shoots the mechanism when the animal steps onto it. Walk the long way between a single response mechanism like that to a response generated by a human brain and you will say it is a different thing.
To add my contribuition to your search of a better nomination of the AI I would call it human designed intelligence as opossed to that intelligence designed by… well, that is another subject!