The phrase "regrettable moment" is correct and usable in written English.
It can be used to describe a specific instance or event that one feels remorseful or disappointed about.
Example: "During the meeting, I made a regrettable moment by interrupting my colleague."
Alternatives: "unfortunate incident" or "sad occasion."
Most Regrettable Moment of Restraint--Jim Carrey, for not adding Babe to the equation.
As an Obama supporter – she hosted a glitzy fundraiser – does she not agree with Freud, even if the story was what she calls a "regrettable moment"?
Never mind that for a regrettable moment even Giorgio Armani and Helmut Lang fell for the credo that "pink is the new black".
In a regrettable moment last weekend, Republican lawmakers proudly took to a House balcony to fan the anger of a throng, some of whom spit on Democratic members and shouted racist and homophobic jeers.
And in this age of smartphones, when there's a slip-up (or, in Missouri governor Jay Nixon's case, when cracks appear) in a campaign, there are dozens of cameras around to capture – and share – the regrettable moment.
Giuliani has been attacking the democrats gravely, but he just served up the first regrettable moment of this debate: it went by too fast, but Mr. Tough Guy Giuliani just responded to the question about going after terrorists by saying something along the lines of we're going to tell them we might consider going after the bad guys if they don't feel like they can do it themselves.
The two-minute web video reads like a manifesto of regrettable moments that have had Democrats giving each other hi-fives for months.
The modern mobile phone — equipped with camera, Internet access and more — has proved to be a liability for some performers, like Akon and Beyoncé, whose regrettable moments were captured by fans and then immortalized on YouTube and similar sites.
The film does not dodge some of Brown's other regrettable moments, though it could be said to downplay them: it shows him beating one of his wives, smoking drugs and being in trouble for not paying his taxes.
If Twitter had existed when Stewart was a snappy, smoking, leather jacket-wearing comic in the '90s, he might have had some regrettable moments, too.
The BBC Trust has described as "unfortunate and regrettable" a moment in an episode of BBC2 quiz show QI in which host Stephen Fry recited a limerick about paedophilia minutes before a Newsnight report on the Jimmy Savile scandal.
