Where does “rosser” come from?

rosser (Norman) comes from Old French roissier, from Vulgar Latin rustiare, from Latin rustia, from Late Latin rustum.

rosser (Norman): to thrash

Definitions

to thrash

Ancestry of “rosser”, step by step

Step	Language	Word	Meaning
1	Old French	roissier	—
2	Vulgar Latin	rustiare	—
3	Latin	rustia	—
4	Late Latin	rustum	—

Every word from Late Latin rustum →Every word from Latin rustia →Every word from Vulgar Latin rustiare →