Sound of a muffled collision between two solid objects (e.g. the sound of two Klingon foreheads colliding, the sound of a falling tree hitting the ground) or a sound with similar auditory qualities (e.g. the sound of a heart valve in a stethoscope).
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When I would translate comic panels, often I would substitute plain Klingon verbs for English onomatopoetic text: paw'! collide! for THUMP! and jor! explode! for BOOM! etc. But a splash and a (stethoscopic) thump are complex enough to warrant their own words, I reckon.
Oh, yes, I tend to do the same thing. I'm translating a novel at the moment where an alien's speech is rendered with onomatopoeia, and for "Boom. Wheeze. Hwssh." I've simply used jor. jev. SuS.
(At one later point I do render "ooom whang hoooof theeeezt" [sic] with actual Klingon sounds because a human character is imitating them, but fortunately 'um wang Huv tlhItlh is clear nonsense in Klingon as well.)
If this ends up being a verb instead of an exclamation, it might be used to express the concept of to throb, maybe in combination somehow with jaghIv rhythm.