Where does “humanitarianist” come from?

humanitarianist (English) comes from English humanitarian, from English humanity, from Middle English humanyte, from Old French humanité, from Latin humanitas, from Latin hūmānus, from Latin homō, from Old Latin hemō.

Ancestry of “humanitarianist”, step by step

humanitarianist traces back through two separate lines of ancestry.

via English humanitarian

StepLanguageWordMeaning
1EnglishhumanitarianConcerned with people's welfare, and the...
2EnglishhumanityMankind; human beings as a group; The human...
3Middle EnglishhumanyteThe condition or behaviour of humans; human...
4Old Frenchhumanitéhumanity; humankind
5Latinhumanitashumanity, human nature; humaneness, humane...
6Latinhūmānushuman (of man, people)
7Latinhomōhuman, person, man
8Old Latinhemō
9Proto-Italichemōman
10Proto-Indo-Europeanǵʰmṓearthling
11Proto-Indo-Europeandʰéǵʰōmearth
12Proto-Indo-European-ōmemphatic suffix or postpositive particle
13Proto-Indo-European-mi

via English ist

StepLanguageWordMeaning
1EnglishistA practitioner or supporter of an ism
2English-istAdded to words to form nouns denoting
3Old French-iste
4Latin-ista-ist; one who practises or believes
5Ancient Greek-ιστήςAlternative form of -τής; -ist
6Ancient Greek-τήςAppended to verbs to form agent nouns
7Proto-Hellenic-tās
Every word from Proto-Indo-European -mi