You may consider "one-off", see http://www.thefreedictionary.com/one-off
Not a teacher.
May I have an adjective describing an experience or a moment which is unique and will NEVER be repeated again?
"Once in a lifetime"
I'd prefer it to be hyphenated if it's an adjective - once-in-a-lifetime.
Last edited by tzfujimino; 19-Mar-2014 at 19:11.