A list of phrases containing the word "once"...
- A once in a lifetime opportunity
- Christmas comes but once a year
- Even a blind hog finds an acorn once in a while
- Fool me once, shame on you, fool me twice, shame on me
- Give it a once over
- I once had a girl, or should I say, she once had me ( The Beatles song lyric )
- If I've told you once, I've told you a thousand times
- If you can't ride two horses at once, you shouldn't be in the circus
- Just this once
- Measure twice, cut once
- Once In A Liftime ( Talking Heads' song )
- Once In Royal David's City ( Christmas Carol title )
- Once Upon A Time In America ( Robert De Niro movie )
- Once a cheater, always a cheater ( the notion that cheats never change their ways )
- Once a thief, always a thief
- Once and for all
- Once and future king
- Once bitten, twice shy
- Once driven, forever smitten ( Vauxhall Motors advertising slogan )
- Once in a blue moon
- Once in a lifetime
- Once in a while
- Once more unto the breach, dear friends, once more
- Once or twice
- Once removed
- Once upon a time
- Once you pop you can't stop ( Pringles advertising slogan )
- Opportunity only knocks once
- Think once, think twice, think bike ( UK Public Information Film advertising slogan )
- Try everything once, except incest and folk dancing ( Sir Thomas Beecham quotation )
- You only live once
- You only live once, but if you do it right, once is enough ( Mae West quotation )
- You're only young once
We are also on 
