Bekk
Bekk or common soldier was the lowest enlisted rank in the Klingon Defense Force. 

When Martok attempted to join the officer ranks of the Defense Force his application was denied by Kor. This action, according to Martok, meant that he could not join the Defense Force "even as a common soldier," and the only way he was allowed to serve the Klingon Empire was to instead join as a civilian laborer. ()

Alexander Rozhenko joined the Defense Force as a bekk in 2374. ()

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de:Bekk
Klingonese
Military ranks