I’ve finally found a couple of wonderful names for those squashed ends on gable roofs that can be found on some of the Honolulu Tudor–French Norman Cottages I’ve been documenting for the WikiProject National Register of Historic Places.
The most fetchingly archaic-sounding terms are jerkinheads or shreadheads. More prosaic (but “hipper”) names for them are clipped gables, hipped gables, half-hips or barn-hips.
As the Wikipedia hip roof article notes, a half-hip is a hip roof on top of a gable roof, while a gablet roof is a gable on top of a hip roof, like the roof type known as irimoya in Japanese.
Irimoya roofs can be seen on a lot of the newer homes built in upper Manoa Valley, whose residents are nowadays far more likely to be of East Asian than European descent.