My spelling checker didn’t like pissant. Stupid spelling checker. It suggested piss-ant. Just to make sure I wasn’t completely insane I consulted my dictionary (oh, dictionary, help me enumerate the ways I love thee…) and sure enough there it was. Origin: the noun piss+ant. So of course I looked up piss. It comes from the Old French verb ‘pisser’, which the dictionary theorizes is imitative of the sound. But then I had “French” and “pissant” in my head at the same time, and I typed in “puissant”, a fine word if ever there was one, and opposed to pissant on more than one axis. Not only do they mean pretty much the opposite, but people who are likely to use one are unlikely to use the other.
A challenge to the muddleverse: a bit of doggerel that will fit in the header above that uses both words, preferably next to one another. You may work individually or in groups.