The story
- Proto-Indo-European*ḱerd-
- Proto-Indo-European*ḱḗr
- Proto-Indo-European*ḱr̥díyeh₂
- Proto-Hellenic*kərdíyā
- Ancient Greekκαρδία (kardía)
- Englishcardio-
- Proto-Indo-European*per-der.?
- Proto-Indo-European*pér
- Proto-Indo-European*pró
- Proto-Indo-European*pro-
- Proto-Italic*pro-
- Latinpro-
- Proto-Indo-European*(s)teg-
- Proto-Indo-European*(s)tégeti
- Proto-Italic*tegō
- Latintegō
- Latinprōtegō
- Late Latinprōtēctiō
- Englishprotection
- English todaycardioprotection
From cardio- + protection.
Etymology from Wiktionary, CC BY-SA 4.0.