Where does “如何しい” come from?

如何しい (Japanese) comes from Japanese 如何, from Old Japanese いか.

Ancestry of “如何しい”, step by step

如何しい traces back through two separate lines of ancestry.

via Japanese 如何

StepLanguageWordMeaning
1Japanese如何what kind of; in what manner, how; what about..
2Old Japaneseいか

via Japanese しい

StepLanguageWordMeaning
1Japaneseしいused to form adjectives from nouns,...

Words derived from “如何しい

Every word from Old Japanese いかEvery word from Japanese 如何