I'm reading one of Wodehouse's later books - "Pearls, Girls and Monty Bodkin". He wrote it celebrate his 91st birthday, but it's as lively and fresh as anything he ever wrote.

Anyway at one point the hero, Monty Bodkin, is in a nightclub being advised by his employer on what to do if the place is raided by the police.

"But I soon learned the lesson that ought to be taght in the schools, and that is that when a bunch of flatfeet burst in with their uncouth cry of 'Everybody keep their seats please,' the thing to do is to iris out unobtrusively through the kitchen."..."It was no idle boast that Mr Llewellyn had made when he spoke of his skill at irising out through kitchens."

Excellent advice, I am, sure, and I am sure we should all take it too heart - but that word "iris" leapt out at me. It is clear enough what it means in general, but it's not a use of the word I have ever come across before, and I am sure that Wodehouse would have had some particular shade of meaning to it.

So has anyone anything to add to enlighten me?   Any other occurrences? Did he just make it up for the fun of it, or was it (or is it still) current in some circles?