There actually is one canon word that seems to be an unsuffixed verb with -ghach: lo'laHghach. Unless you consider it a nominalization of lo'.

I seem to recall Okrand saying a bare verb stem plus -ghach is something that might occur in jargon, so *jeDghach could be scientific jargon for viscosity (or less likely, for density).

Okrand says:

It's a highly marked form. It's a word you are forming for a specific occasion and a specific effect. If you were a poet or philosopher or hard scientist and had to describe something very specifically these kinds of words might be appropriate but it carries the feeling of very technical arcane vocabulary, not normal everyday stuff. So can you say it? Yes, but you are saying more, rather than less or neutral.

It's not that -ghach occurs on bare stems in scientific jargon; it's that a scientist trying to explain something arcane that doesn't already have a word might throw -ghach on a bare verb to make a point. You're coining a word of the moment, not finding it in a textbook.

Basically, the effect of -ghach on a bare verb is the same as putting scare-quotes around a word you just made up.

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SuStel
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