Battle Language was a variant of the Klingonese languages which used abbreviated words and grammar.
History and specifics[]
It was typically used in combat situations, hence its name. (TOS - Worlds Apart novel: The Final Reflection)
In the year 2281, T'Shael said the word for "light" in Battle Language and successfully turned on the lights in the room that she and other Warrantors of Peace were held in. (TOS novel: Dwellers in the Crucible)