Klingon ranks
The rank system of the Klingon Defense Force provided a hierarchy and chain of command for Klingon warriors and officers. 

Should the an officer become weak and unable to perform their duties, it was expected of the next in line to assassinate them to ensure an "honorable retirement," such as a first officer killing a commanding officer, or a second officer killing the first officer. By the 2360s, the system had been considered successful for centuries, though was noticably different from Starfleet's approach. ()

Fleet admiral 

During the 22nd century, the rank of fleet admiral existed, and was sometimes shortened to "admiral". This rank was indicated to be superior to that of a general. ()

 Fleet Admiral

General 

Generals were flag officers who fulfilled roles ranging from the commanding officer of a warship, to a diplomat, to a supreme commander of a fleet, to a chief of staff. (; ; )

 General 
 General K'orin
 General K'Trelan
 General K'Vagh
 General 
 General Korrd
 General Martok
 General ShiVang
 General Stex
 General Tanas

Brigadier 

A brigadier was a high ranking official who could handle the position of military advisor to the Chancellor, and could speak on behalf of the High Command. ()

 Brigadier Kerla

Colonel 

Colonel was high ranking position that could fulfill the role of advocate or serve as a diplomat.

 Colonel

Captain 

Captains in the Klingon Defense Force commanded individual warships of all classes. 

 Captain K'Temang
 Captain K'Temoc
 Captain K'Vada
 Captain Kargan
 Captain Klaa
 Captain Koloth
 Captain 
 Captain Korris
 Captain Kurn
 Captain 
 Captain Lurkan
 Captain Nu'Daq

Commander 

Commanders in the Klingon Defense Force commanded individual ships of all classes of warship. An individual holding the rank of commander could also hold the position of military governor. ()

 Commander Kang
 Commander Kaybok
 Commander Kolana
 Commander Kor
 Commander Kruge
 Commander Kuri
 Commander Morag
 Commander Sorval

Lieutenant 

Lieutenant was a junior officer rank aboard warships. 

On a Bird-of-Prey, a lieutenant could hold the position of second officer. ()

When confronted by an inquisitive lieutenant aboard the  during an infiltration operation, Lieutenant Commander Worf – who was posing as Commander Sorval – rebuffed his line of questioning by stating, "I will not be questioned by a lieutenant who should be cleaning my quarters." ()

 Lieutenant 
 Lieutenant Konmel
 Lieutenant Laneth
 Lieutenant Synon

Sergeant 

 Unnamed Klingon sergeant

Bekk 

Bekk was an enlisted rank that was also commonly referred to as a "warrior." It was the lowest rank in the Klingon Defense Force. ()

 Bekk Koth
 Bekk N'Garen
 Bekk Alexander Rozhenko

Appendix

Background information 
This rank system combined army ranks (general, brigadier, colonel, and possibly captain and lieutenant) with navy terminology (ship captains, commanders, and lieutenants).

The Klingon Dictionary translates the ranks of cadet (mangHom), ensign (lagh), sergeant (bu), lieutenant (Sogh), commander (la; rawI), captain (HoD), commodore (totlh), brigadier (ech), general (Sa), and admiral (aj). (pp. 81, 123, 125, 134, 186-189)

The Star Trek: The Next Generation Technical Journal (p. 79) suggests the two emblems on the Klingon Defense Force uniform collar are rank insignia, though their use on screen has not necessarily been consistent.

External link
 

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