The character for long 'o' in a Japanese names means "big." The (most common) character for short 'o' in a Japanese names means "small." For example, 大野 is "oono," literally "big field." 小野 is "ono," literally "small field." Both are fairly uncommon (but not exactly rare) Japanese surnames belonging to on the order of middle tens of thousands of Japanese people (the most common names in Japan belong to somewhere between half a million and a million).
So, was Yoko Ono big or small? I don't happen to know.
I am amused by small things. Or possibly big ones.