What does am oesru mean in french?

"Am oesru" is not a French phrase. It appears to be a misspelled or incomplete phrase. It's possible that it's a misspelling of a Welsh phrase, as "oesru" could be a variation of the Welsh word "oes" meaning "age" or "era."

Could you please provide more context or information about where you encountered this phrase? This will help me understand what you're trying to convey and offer a more accurate translation.