Where does “underplate” come from?

underplate (English) comes from English plate, from Old French plate, from Medieval Latin plata, from Vulgar Latin plattus, from Ancient Greek πλατύς, from Proto-Indo-European pléth₂us, from Proto-Indo-European pleth₂- — flat.

underplate (English): An armoured plate that forms part of a mortice...

Definitions

  1. An armoured plate that forms part of a mortice...

Ancestry of “underplate”, step by step

underplate traces back through two separate lines of ancestry.

via English plate

StepLanguageWordMeaning
1EnglishplateA slightly curved but almost flat dish from which...
2Old Frenchplatea flat metal disk; a flat plate of armor
3Medieval Latinplatasilver
4Vulgar Latinplattusflattened; flat; smooth
5Ancient Greekπλατύςwide, broad; flat, level; broad-shouldered
6Proto-Indo-Europeanpléth₂usflat, broad
7Proto-Indo-Europeanpleth₂-flat

via English under

StepLanguageWordMeaning
1EnglishunderIn or at a lower level than; As a subject of;...
2Middle Englishunderunder
3Old Englishunderunder, beneath
4Proto-Germanicunderamong, between; under, beneath; under
5Proto-Indo-Europeanh₁entérbetween
6Proto-Indo-Europeanh₁enin; in, inside
Every word from Proto-Indo-European pleth₂-Every word from Proto-Indo-European pléth₂usEvery word from Ancient Greek πλατύς