This is one of those terms that could make your eyes cross, but when you come right down to it, it pretty much defines itself. Think of “nonrestrictive” as “non-essential”, which is not actually the technical definition. It’s giving extra or parenthetical information. Here’s the technical definition : Restrictive clauses limit the possible meaning of a preceding subject. Nonrestrictive clauses tell you something about a preceding subject, but they do not limit, or restrict, the meaning of that subject. Okay, let’s see an example to make it more user-friendly. The suspect in the lineup, who owns a red car, committed the crime . The sentence makes sense without the phrase “who owns a red car” and doesn’t actually “need” that qualifier. It’s not essential to the crime in this case to know he owns a red car. However, The suspect in the lineup who has red hair committed the crime is a “restrictive clause, because it IS essential to the meaning of the sentence. We know it’s not the s...