Where does “ヘプタスロン” come from?

ヘプタスロン (Japanese) comes from English heptathlon, from English hepta-, from Ancient Greek ἑπτά, from Proto-Hellenic heptə́, from Proto-Indo-European septḿ̥ — seven.

Ancestry of “ヘプタスロン”, step by step

StepLanguageWordMeaning
1EnglishheptathlonAn athletic contest comprising seven events;...
2Englishhepta-API; seven
3Ancient Greekἑπτάseven
4Proto-Hellenicheptə́seven
5Proto-Indo-Europeanseptḿ̥seven
Every word from Proto-Indo-European septḿ̥Every word from Proto-Hellenic heptə́Every word from Ancient Greek ἑπτά
ヘプタスロン — Etymology, Origin & Word History | Etymology Explorer