The story
- Proto-Indo-European*bʰeg-der.?
- Proto-Germanic*baką
- Proto-West Germanic*bak
- Old Englishbæc
- Middle Englishbak
- Englishback
- Middle Englishcheteren, chiteren (Imitative)
- Middle Englishchateren
- Englishchatterclip.
- Englishchat
- English todaybackchat
Etymology from Wiktionary, CC BY-SA 4.0.