means a person trained and licensed to practice law, advising clients and arguing their cases in legal matters

from From Middle English lauier, lawer — simply 'one who works with law.' The word law itself comes from Old English lagu, borrowed from Old Norse lag, meaning something 'laid down' or fixed in place — the same root sense as things laid flat or settled. So a lawyer is, at heart, a worker of what has been laid down: a tender of fixed rules.