English

mainplate

main + plate

A compound of main + plate

Middle English mayn

English main

Proto-Indo-European *pleth₂- ‘flat’

…

Vulgar Latin *plattus ‘flat’

Medieval Latin plata

Old French plate ‘a flat metal disk’

Middle English plate

English plate

Today it means

noun The base plate of a watch movement that holds all the parts in place.

Language periods are conventional ranges, not dates for this word.

Etymograph / mainplate