Where does “trapfall” come from?

trapfall (English) comes from English trap, from Middle English trappe, from Old English træppe, from Proto-Germanic trap-, from Proto-Indo-European dreb-, from Proto-Indo-European der- — to split, to separate; to tear, to crack, to...

Ancestry of “trapfall”, step by step

trapfall traces back through two separate lines of ancestry.

via English trap

StepLanguageWordMeaning
1EnglishtrapA machine or other device designed to catch (and sometimes kill) animals, either by holding them in a container, or by catching hold of part of the body
2Middle Englishtrappetrap
3Old Englishtræppea trap
4Proto-Germanictrap-
5Proto-Indo-Europeandreb-
6Proto-Indo-Europeander-to split, to separate; to tear, to crack, to...

via English fall

StepLanguageWordMeaning
1Englishfall"To be moved downwards."; "To move downwards.";...
2Middle Englishfall
3Old EnglishfeallAlternative form of fiell
4Proto-Germanicfallą
5Proto-Indo-European(s)pōl-to fall
Every word from Proto-Indo-European der-Every word from Proto-Indo-European dreb-Every word from Proto-Germanic trap-