lady

Concise Oxford English Dictionary © 2008 Oxford University Press:
lady/ˈleɪdi/

▶noun (pl. ladies)

• 1 (in polite or formal use) a woman.

• 2 a woman of superior social position.

  ■ (Lady) (in the UK) a title used by peeresses, female relatives of peers, the wives and widows of knights, etc.

  ■ a courteous or genteel woman.

• 3 (one's lady) dated a man's wife.

  ■ historical a woman to whom a knight is chivalrously devoted.

• 4 (the Ladies) Brit. a women's public toilet.

– phrases
find the lady another term for three-card trick.
it isn't over till the fat lady sings there is still time for a situation to change. [by assoc. with the final aria in tragic opera.]
Lady Muck see muck.
My Lady a polite form of address to female judges and certain noblewomen.

– derivatives
ladyhood noun.

word history: The forerunner of the word lady in Old English was hlǣfdīge, meaning the female head of a household, or a woman to whom homage or obedience was due, such as the wife of a lord or, specifically, the Virgin Mary. The word came from hlāf ‘loaf’ and a Germanic base meaning ‘knead’ which is related to dough and dairy; thus a lady was a ‘loaf kneader’. The word lord developed in a similar way; in Old English it literally meant ‘bread keeper’.