The most common and most likely answer to this crossword clue is the 3 letter word ERA
I've seen this crossword clue in The Times
E
R
A
More clues leading to the result ERA
- One reigning over a long period
- Don’t start off one such as Lynn. Period
- Artist depressed by ultimately blue period
- Period covered by Northanger Abbey
- Some other age and time
- English artist showing age
- Time is, for more than one person, up
- Age of eastern artist
- A long time shut up in seraglio
- Important date in October added
Buddy explains!
The straight part
We know that "A long time" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case a long time = era.The cryptic/wordplay part
In cryptic crossword there's often an wordplay/cryptic part as well.This part involves a more complex hint, such as an anagram, homophone, hidden word, etc.
Sadly, We don't have an explanation for this specific crossword clue yet.
What does ERA mean?
ERA noun- A time period of indeterminate length, generally more than one year.
- A unit of time, smaller than eons and greater than periods.