Merriam-Webster's Collegiate® Dictionary, 11th Edition
LUCK
I. noun
Etymology: Middle English lucke, from Middle Dutch luc; akin to Middle High German gelücke luck
Date: 15th century
1. a force that brings good fortune or adversity, the events or circumstances that operate for or against an individual, favoring chance, luckless adjective
II. intransitive verb
Date: circa 1584
to prosper or succeed especially through chance or good fortune, to come upon something desirable by chance