Will-o'-the-wisp

WORD OF THE DAY

will-o'-the-wisp \ will-uh-thuh-WISP \ noun

Definition
1 : a light that appears at night over marshy ground
2 : a misleading or elusive goal or hope

Examples
"Why don't you try to communicate with your boyfriend and see if you can find the root of the dissatisfaction? Perhaps you can repair it before you go and dismantle your life. If the relationship has run its course, you know what you have to do. But do it for yourself, not for a 23-year-old will-o’-the-wisp." 
— Molly Ringwald, The Guardian, 12 December 2014

"While a company's purpose generally doesn't change, strategies and organizational structures do, which can make chasing 'alignment' between strategy and the organization feel like chasing an elusive will-o'-the-wisp." 
— Jonathan Trevor and Barry Varcoe, Harvard Business Review (hbr.org), 16 May 2016

Did You Know?
The will-o'-the-wisp is a flame-like phosphorescence caused by gases from decaying plants in marshy areas. In olden days, it was personified as "Will with the wisp," a sprite who carried a fleeting "wisp" of light. Foolish travelers were said to try to follow the light and were then led astray into the marsh. 
(An 18th-century fairy tale described Will as one "who bears the wispy fire to trail the swains among the mire.") The light was first known, and still also is, as ignis fatuus, which in Latin means "foolish fire." Eventually, the name will-o’-the-wisp was extended to any impractical or unattainable goal.