As a girl's name this is a pet form of Jacqueline, as in the case of Jackie Kennedy Onassis (1929–94). It was originally a boy's name, a pet form of Jack. The racing driver Jackie Stewart (b. 1939) was originally named John Young Stewart.
English: habitational name from any of the various places called Morley (for example in Cheshire, Derbyshire, County Durham, Norfolk, and West Yorkshire), or Moreleigh in Devon, all of which are named from Old English mōr ‘marsh’, ‘fen’ + lēah ‘woodland clearing’.