Just asked my wife, and she said that it's called 'knocking back', or 'punching down'.

Have a look here: 'Similar to kneading is knocking back or punching down, which is done to the dough after proving. The dough is punched once or twice, after which it is kneaded gently for a short time. The aim of this is to remove any large air pockets which have formed in the dough, create an even texture in the bread and redistribute the nutrients for the yeast, thus allowing fermentation to continue. The dough can then be proved a second time. Another method of knocking back (also known as "folding") is to gently stretch and pat out the proved dough before folding the sides in towards the centre.' (http://en.wikipedia.org/wiki/Kneading )

'Question: What is meant when a bread recipe asks you to 'knock back' the dough?

Answer: Knocking back the dough is often termed punching down the dough. Just give it a good jab with your fist a couple of times and a bit of a knead to get all the extra air out so you can shape it.'

(http://uk.answers.yahoo.com/question/index?qid=2008021307575... )