The story
- Proto-Indo-European*dwóh₁
- Proto-Indo-European*trísinflu.
- Proto-Indo-European*dwís
- Ancient Greekδιά (diá)
- Ancient Greekδια- (dia-)
- Proto-Indo-European*h₂esp-der.?
- Latinasper
- Ancient Greekἄσπρος (áspros)
- Medieval Greekδίασπρος (díaspros)
- Medieval Latindiaspra
- Old Frenchdyapre
- Middle Englishdyaper
- Englishdiaper
- Proto-Indo-European*sek-
- Proto-Indo-European*séks-u-s
- Proto-Italic*seksus
- Proto-Indo-European*sek-
- Proto-Indo-European*sékh₁yeti
- Proto-Italic*sekaō
- Latinsecō
- Latinsecāre?
- Latinsexus
- Old Frenchsexe
- Middle Englishsexe
- Englishsex
- English todaydiapersex
From diaper (“an absorbent garment”) + sex (“sexual activity, such as intercourse or another sex act”).
Etymology from Wiktionary, CC BY-SA 4.0.