Yeah, the definitions do not explain the origins. Good sources of etymology are VERY limited. I reckon this project of mine will take me 5-7 years, depending on when I will be able to stop working in the office, and focus on something meaningful instead...
I would like to specilize in seal script, inluding kinbun and oracle bone. I want to continue its research in the future. But this will take some time.
Seal script is essencial for seal carving, which is also within my interest. Without knowledge of seal script one cannot read / carve seals. Lastly, with the knowldge of seal script, one better understands clerical and other scripts, as seal script is the father of them all. Many characters were deformed/simplified after unification of seal script in 221 BC.
I am gropping in the dark, but since 御 also means to resist and defend, it may be possible that "to use a horse, i.e. drive a chariot" was a meaning derived from its military connotation. Yeah, man, kanji is a jungle. Totally awesome invention.
And since 中華字海 lists nearly 83 000 characters, its a very thick jungle.