Pronunciation: [ ih-fem-er-uh ]
Definition: noun
things that exist or are used or enjoyed for only a short time.

Origin: 1670-80
Etymology: Greek ephḗmera, neuter plural of ephḗmeros, taken as singular
Usage:

Synonyms:
object
curio
oddity
Antonyms:
enemy
manager
opponent
owner
Example: Elton has a large collection of old menus and other ephemera.