MEANING: noun:
1. A unit of length equal to the distance traveled by light in one year in a vacuum, about 5.88 trillion miles or 9.46 trillion km.
2. Very far, in distance or time.

ETYMOLOGY: From light, from Old English leoht + year, from Old English gear. Earliest documented use: 1888.

NOTES: A light-year is a unit of distance -- there’s no such unit as a heavy-year (nor is there a dark-year). To get a light-year’s worth of frequent-flier miles you’d need to travel between New York and Moscow only a little over a billion times.

MIGHTY EAR - what it takes to hear a pin drop

FLIGHT-YEAR - how long a trip to Mars in an elliptical orbit would take

EIGHT-YEAR - a long-term car lease