1.
An ~ computer program or television system is one which allows direct communication between the user and the machine.
This will make videogames more ~ than ever.
ADJ
interactivity
...cable broadcast companies that offer interactivity.
N-UNCOUNT
2.
If you describe a group of people or their activities as ~, you mean that the people communicate with each other.
...flexible, ~ teaching in the classroom.
ADJ