Where does “赤道ギニア” come from?

赤道ギニア (Japanese) comes from Japanese ギニア, from English Guinea, from Portuguese Guiné, from English -ia, from Latin -ia, from Latin -ius, from Proto-Italic -jōs, from Proto-Indo-European -yós — Creates adjectives from noun or verb stems.

Ancestry of “赤道ギニア”, step by step

赤道ギニア traces back through two separate lines of ancestry.

via Japanese ギニア

StepLanguageWordMeaning
1JapaneseギニアGuinea
2EnglishGuineaA gold coin originally worth twenty shillings; later (from 1717 until the adoption of decimal currency) standardised at a value of twenty-one shillings
3PortugueseGuinéGuinea
4English-iaUsed in forming names of countries, diseases,...
5Latin-iaUsed to form a feminine abstract noun, usually...
6Latin-iusforming adjectives from nouns; nominative neuter...
7Proto-Italic-jōsForms comparative adjectives
8Proto-Indo-European-yósCreates adjectives from noun or verb stems

via Japanese 赤道

StepLanguageWordMeaning
1Japanese赤道equator
2Chinese赤道celestial equator; equator

Words derived from “赤道ギニア

Every word from Proto-Indo-European -yósEvery word from Latin -iaEvery word from Latin -ius