The word menhir come up in discussion yesterday and I posted it on Facebook today along with the the Welsh translation maen hir, which is what I found in this dictionary. This provoked further discussion about whether the two terms mean the same thing. So I thought I’d find out.
A menhir is a standing stone of the kind that Obelix delivers in the Asterix books. According to the Dictionary of Word Origins and the OED, menhir comes from Breton mean-hir (long stone), which is what the Welsh term maen hir means, so it seems that they are the same. The usual Breton word for such standing stones is peulvan, however.
The word dolmen (a prehistoric structure of two or more upright stones surmounted by a horizontal one), comes via French from Breton: the men part means stone, and the dol part either comes from the Breton word tōl (table), a borrowing from the Latin tabula (board, plank), or from the Cornish tol (hole). So dolmen either means ‘stone table’ or ‘stone hole’.
The word dolmen also exists in Welsh, and another word for such structures is cromlech, which exists in Welsh and English and comes from the Welsh words crwm (bent, stooped) and llech (stone), and is related to the Irish word cromleac (‘bent stone’).