For a userscript I’m working on, I created a list of all synonyms (kanji and vocabulary separately), which just contains all meanings and the corresponding kanji/vocab which share this meaning (any kind, primary or auxiliary). There was a forum post some time ago asking for such a synonym chart, but as far as I could see there was no such list. So here it is. I can also publish the corresponding data with IDs in JSON format and the code I used to compute the list, if people are interested. I hope I’m not breaking any rules posting API content like this.
I am going to post the list in a second post, because it is rather long. By the way, the meaning with the most kanji synonyms (5) is “I” (私, 我, 俺, 僕, 吾), and the one with the most vocab synonyms (11) is “support” (助力, 支援, 応援, 賛成, 維持, 後ろ盾, 対応, 擁護, 擁立, 扶助, 扶養).
Thanks! It should be fixed now. Kanji/vocab with numbers attached were apparently hidden from WaniKani, I’m now filtering hidden subjects with the proper API attribute and I’m using the correct characters for each subject.