You searched for: “most atokous
atokous (adjective), more atokous, most atokous
Descriptive of someone or something that cannot produce offspring: Atokous animals may become nonproductive because of some form of sterility process, such as dogs, cats, bulls, etc.

There are those who become atokous by having their reproductive organs removed, either by choice or because they have genetically transmissible disabilities, etc.

Other atokous examples include making some plants incapable of bearing fruit or germinating, or the rendering of land that makes it unfruitful because of chemicals, excessive salt, etc.