There is a Wikipedia site dealing with unparliamentary language in various countries around the world, what cannot be said by one member of a legislature against another. Unfortunately as regards the United States it is unspecific.
However in the United Kingdom's House of Commons the following expressions have been deemed to be unparliamentary, at different times. One assumes that similar expressions are unacceptable in the US Senate.
blackguard, coward, deceptive, dodgy, drunk, falsehoods, git,
guttersnipe, hooligan, hypocrite, idiot, ignoramus, liar, pipsqueak, rat,
swine, stoolpigeon, tart, traitor, sod, slimy, wart
In addition, accusations of 'crooked deals' or insinuation of the use
of banned substances by a member are considered unparliamentary
language (all attributable to Dennis Skinner).
The word 'dodgy' when used by Ed Miliband, was not however, found to