The origin of the geoduck is a pretty stubborn one. The geoduck race is so stubborn that it refused to evolve into an animal that made any sense. Hence, the origin of the geoduck is one of stubbornness.
You know who else was stubborn? Gandhi (がん). Gandhi believed in non-violent resistance and he was pretty stubborn about it.
Currently there are no similar looking kanji which exist in the WaniKani learning system