Nemo me impune lacessit

Nemo me impune lacessit is the Latin motto of the Most Ancient and Most Noble Order of the Thistle, the Scottish chivalrous order.

It means "No one attacks me with impunity", or in Scottish Gaelic "Cha togar m' fhearg gun dìoladh", in Scots "Wha daur meddle wi me?", or in Glaswegian "See you Jimmy, goup at me an' I'll tear yer heid aff!"