Tokubetsu Jōnin

are ninja who, rather than having all-around jōnin skills, they only excel in a specific area, much like warrant officers in real-world militaries. For example, Ibiki Morino can completely understand the workings of the human mind, making him an expert in interrogation. They are elite specialists in their areas and are often assigned as subordinates to regular jōnin when their services are needed.

Trivia

 * In Naruto: Rise of a Ninja, tokubetsu jōnin are called elite shinobi.