Statement of research interests
For academic positions, you will often be asked for a 'statement of research interests' or similar. Generally, a word limit will be specified although these can vary enormously.
As with all aspects of your application, make sure you re-write your statement of research interests for each application. In all likelihood, your research interests are broad enough to be tailored to local interests and expertise. Make sure that there is substantial overlap between what the employing department is looking for in terms of research and your own. This is worth the substantial time investment.
Probably the best way of doing this is to talk with people in the department you are applying to. This will raise your profile and allow you to network with potential future colleagues (who will more than likely enjoy the opportunity to explore potential new research avenues) and opportunities and appreciate being asked).