Europe's responsibility in this entire area is not easily defined, however.

It is a term often used, probably pretty well understood, but not easily defined.

Frequently, they cannot be easily defined by a particular geographical area.

Users can easily define their own control structures as well.

He is easily defined by what he's not, because the whole film seems to have crucial pieces missing.

Good faith is not easily defined, despite being a common concept in the Roman law.

The era was long, complicated and is not easily defined by sound bite.

Moreover, the line between legality and security is not easily defined.

Of course, the quality of an executive is not always easily defined.

The terms language and dialect are not easily defined concepts.