Answer:

eonian

Answer	Crossword Clue
EONIAN	Of a long, long time
EONIAN	Very long term
EONIAN	Everlasting.

EONIAN	Everlasting
EONIAN	Eternal
EONIAN	Long-lasting
EONIAN	Lasting a long, long time
EONIAN	Lasting a very long time
EONIAN	Lasting a long time
EONIAN	Lasting forever
EONIAN	Interminable

Crossword

a puzzle consisting of a grid of squares and blanks into which words crossing vertically and horizontally are written according to clues.