This phrase popped into my head the other day and I realized that I haven’t heard it for years and years.
There are two meanings or interpretations of it:
1) a futile act
2) a not-so-delicate way of asking someone to go away.
The way I remember it being used was with the latter meaning.
It is similar to some chiefly British phrases, like ‘pissing in the wind,’ and ‘to piss about.’ Both of these mean that one is wasting time, but to ‘piss in the wind’ can also be taken to mean doing something silly, perhaps even counter-productive.
If anything can be seen as more futile or more stupid than pissing into the wind, that would be attempting to urinate up a vertical rope. If the wind can throw it back at you, what will gravity most certainly do with it? And your continued urination will only splash the resulting mess more widely. Pissing up a rope is about as silly as it gets.
As for asking someone to go away, the phrase has been replaced by the shorter and now ubiquitous ‘piss off,’ which is the more polite version of that invitation.
All this rumination made me finally look up the meaning of ‘pissant,’ a word I’ve read, though never heard spoken, and never was sure of the meaning.
My Random House Unabridged (why do I always want to say ‘unadulterated’?) Dictionary says, “Slang (vulgar) A person or thing of no value or consequence; a despicable person or thing.” It dates back to about 1655 and appears to be a combination of ‘piss’ (because urine smells like the formic acid ants produce), and ‘ant.’
So now I know!