domain; sphere; field; territory; area

They want to talk to you about areas of mutual interest.

There is a place in this world where we cannot and must not set foot. Knowing of this existence, to accept it and show it the greatest reverence is the first step to belief.

Let us remember that if this financial crisis taught us anything, it's that we cannot have a thriving Wall Street while Main Street suffers.

What's your major field?

The discovery that electric currents can be produced by magnetism is extremely important in the field of electricity.