Jisho

病気 is not a verb. What did you enter?

I guess you used this as a search term: https://jisho.org/search/%E7%97%85%E6%B0%97%20%23verb (Really you need to include that information in case you want to talk about it). And now you're wondering why this search also includes the entry https://jisho.org/word/%E7%97%85%E6%B0%97 in the results list even though it does not have a verb tag.

To understand this let's take a look at the underlying database entry at https://www.edrdg.org/jmwsgi/entr.py?svc=jmdict&sid=&e=2281536 and take note especially at the history log of that entry and the changes it went through. You can see this entry used to have a "vs" pos tag. (A Pos tag meaning part of speech info, and vs meaning "noun or participle which takes the aux. verb suru").

Unfortunately apparently these old tags don't get purged from the search index at Jisho.org even if the underlying entry has changed in the meantime. You can see that the entry also shows up when searching specifically for https://jisho.org/search/%E7%97%85%E6%B0%97%20%23vs even though there is no "vs" tag anymore.

So to answer your question. No, the entry is not a verb. Meaning 1 and 2 are tagged as nouns, meaning 3 is tagged as no-Adjective and as colloquial usage. It does however show up in a search at Jisho.org even if you filter for verbs because of how the underlying database / search algorithm is designed. Maybe this is something that will get fixed in the future. I think it came up before on the forums, so Kim should be aware.

Ah I see. I just entered "#verb" into the search bar, and 病気 is one of them which is the reason of the post.

Thanks for the detailed reply!