Where does “tricuspid” come from?

I need to work through this carefully, as the chain provided seems problematic. The chain given is: - English cuspid | Latin cuspis | Latin tres | English three | Proto-Indo-European tréyes | Proto-Indo-European tréyes | Proto-West Germanic þrīʀ | Proto-Germanic þrīz This chain doesn't make logical sense. It appears to mix: 1. A path from "cuspid" (Latin cuspis = point/sharp) 2. Then jumps to "tres/three" (meaning three) 3. Then continues with the "three" etymology The word "tricuspid" should derive from: - Latin "tri-" (three) + "cuspid-" (from cuspis, point) So the actual chain should be something like: English tricuspid ← Latin tricuspis ← Latin tri-

tricuspid (English): Having three cusps, e.g. a molar tooth;...

Definitions

  1. Having three cusps, e.g. a molar tooth;...

Ancestry of “tricuspid”, step by step

tricuspid traces back through two separate lines of ancestry.

via Italian tricuspide

StepLanguageWordMeaning
1Italiantricuspidetricuspid
2Italiancuspidecusp; spire
3Latincuspispoint, tip; spit; sting
4Proto-Indo-Europeanspey-sharp point, stick

via English cuspid

StepLanguageWordMeaning
1EnglishcuspidA tooth with a single cusp; a canine

Words derived from “tricuspid

Every word from Proto-Indo-European spey-Every word from Latin cuspisEvery word from Italian cuspide