zulcarna left-rotates Why left? Well... why not?
Given the important associations of abnormal & somewhat suspect,
tolfadni (or tolslabu) te carna, 'opposite-of-ordinary/ opposite-
of-familiar direction-of-turning' was what I had in mind. (Lojbanists
occupy much of their time in trying to come up with things that are
hard to say in Lojban.)
It is traditional in Science and Math to use the "right-hand" rule; clockwise rotation around an axis sticking out of the page (or the skami screen) is known as 'in' to the page; counter-clockwise is 'out' of the page. Stare at the relationship between your thumb and the other 4 fingers of your right hand to figure out why. Oh yes indeedy
Or, if you are partial to wine, think how a cork-screw works ; even if you're not, this is the usual way to unscrew anything — mi'e greg.
dutkemsolryfarna 'opposite-sundirection'.
I (=And) don't see why "left-rotate" isn't obvious. You walk widdershins round something, you have your left side nearest it.