Where does “sexistic” come from?

sexistic (English) comes from English sexist, from English sex, from English sect, from Middle English secte, from Old French secte, from Late Latin secta, from Latin sequi, from Latin sequor — to follow; to see; to say.

Ancestry of “sexistic”, step by step

sexistic traces back through two separate lines of ancestry.

via English sexist

StepLanguageWordMeaning
1EnglishsexistA person who discriminates on grounds of sex;...
2EnglishsexA category into which sexually-reproducing...
3EnglishsectAn offshoot of a larger religion; a group sharing...
4Middle EnglishsecteA variety or sort; a category with a...
5Old Frenchsectea sect in philosophy or religion
6Late Latinsectaa sect in philosophy or religion, a school,...
7Latinsequipresent active infinitive of sequor; follow, come...
8LatinsequorI follow, come or go after
9Proto-Italicsekʷōrfollow, come/go after
10Proto-Indo-Europeansékʷetorto be following
11Proto-Indo-Europeansekʷ-to follow; to see; to say

via English ic

StepLanguageWordMeaning
1Englishicrelated or pertaining to; having the character of
Every word from Proto-Indo-European sekʷ-Every word from Proto-Indo-European sékʷetorEvery word from Proto-Italic sekʷōr