Osoto gari translates to "large outer reap". That makes perfect sense as it is a large reap on the outer leg.
Osoto guruma translates to "large outer wheel" and the "wheel" part eludes me.
What exactly is a "wheel"?
Disclaimer: I am a judo ikkyu who prefers
Judo throws are named and grouped by their telltale action. That is, the names are a pedagogical tool to delineate the various body mechanics one can use to throw an opponent. That's why such fine distinctions are made between, say,
Keeping that in mind, it is important to distinguish
This distinction is apparent when one compares
Ben Reinhardt, esteemed judoka, describes the
(A henka is a variation.) The interplay between
From my point of view, o-soto-gari is throwing uke toward his back. You bend Uke's so his weight is on a leg, and you reap that leg.
in osotoguruma, your leg act as a pivot, and you rotate him over it. You'll see it done in competition very differently than in practice : you take Uke, and pulls him toward you, and you rotate at the same time. While he follow your rotation, you turn and set your leg high on his side, almost to his hip, and you flip him over it. The leg isnt reaping, its only a pivot. Kinda hard to describe, but pretty obvious when you see it.
If the image below describes the technique accurately, I would say it is because uke's legs form a wheel (or a circle) in the air. However, I have no official source for this.