1. a short-lived organism or thing; something that lasts only a very brief time
Usage: often used in scientific or literary contexts; plural: ephemera or ephemerons
2. a mayfly or other insect with a very short adult lifespan
Usage: entomological term; plural: ephemera or ephemerons

Examples

• The beauty of cherry blossoms is an ephemeron, lasting only a few weeks each spring.
• Social media trends are often ephemerons, disappearing as quickly as they appear.
• The mayfly is a classic ephemeron, living as an adult for just one day.
• Fashion fads are ephemerons that fade from popularity within months.
• The artist created ephemerons—temporary installations meant to exist briefly and then vanish.
• In nature, many insects are ephemerons with lifespans measured in hours or days.