Despite a surfeit of serious news, the political firmament has found time to be gripped by Prime Minister John Key's recent verbal infelicities.

In Parliament yesterday, Winston Peters decided it was time he had his mouth at least figuratively washed out with soap.

In prosecutorial tones, he asked how the prime minister could retain confidence in a minister who had insulted an accomplished sportsman and philanthropist, and sworn in front of children.

However, it was tricky for the NZ First leader to administer paddywhacks without himself repeating the offences: calling a man's red top "gay", and referring to football star David Beckham being "as thick as batshit".

"Let's hear from Precious!" mocked National's Nick Smith as Mr Peters approached his wrathful perorations.

"Well, we wouldn't want to hear from Dopey, would we?" Mr Peters snapped back.

In the event, he coped with "gay", but resorted to "bat scatology" rather than repeat the swearword. But his conclusion was clear: the prime minister should sack himself.

However, Mr Key was sticking to his line, that the reported comment about Beckham was hearsay and not to be relied upon.

Mr Peters asked him straight: did he say "thick as bat-and-you-know-what-the-rest-was", or not?

"Categorically, I did not say that, no," Mr Key said.

The House was now quite excited, as Mr Key had never so frontally denied the quote before. But was he denying "bat-and-you-know-what-the-rest-was" or "thick" or both?

Before Mr Peters could ask, however, Speaker Lockwood Smith ruled he had used up his party's daily quota of five questions. Mr Peters disputed this, but Dr Smith insisted on his own ability to count to five.

Labour's Trevor Mallard then sought leave to gift Mr Peters one of Labour's questions "in order for him to be able to ask whether the shit word was used or not".

Dr Smith shrewdly interpreted this as a cheeky Mallard ploy to say the offending word in Parliament himself, rather than a genuine offer of help, and grumpily refused the question transfer.

There was a false dawn when Mr Key offered to clarify matters. "I am reluctant to swear in Parliament, but if [Mr Peters] is asking me whether I used the word ‘batshit', I did not."

Alas, this left more questions than it answered. He had not denied saying some other vernacular form of the word, using bull, horse, pig or chicken.

And perhaps more importantly, he had not denied using the word "thick", essentially the most insulting element of the reported quote.

And had he confirmed "thick" but disputed the nature of the "shit", it would be important for the House to know whether he had used a form of it of greater or lesser viscosity than that produced by bats, as that would affect the severity of the insult.

Frustratingly, Labour seemed to be having a thick spell itself.

It had enough questions left to have asked Mr Key what he now claimed to have said instead. But not one of its MPs had that bright idea, and Dr Smith called the next question, leaving the mystery of the scatology, of the genus chiroptera or otherwise, unsolved.