The story
Sobremesa is Spanish for the time spent at the table once the meal is over. It is built from sobre, 'over' or 'upon', and mesa, 'table'. The plates go, coffee arrives, perhaps a small glass of liqueur or aguardiente, and nobody gets up.
In Spain this is an ordinary part of a long lunch at the weekend or on a holiday, and restaurants allow for it. The word has a second life on television: the sobremesa slot, the early afternoon after lunch, is one of the main viewing times of the Spanish day.
What makes it hard to put into English is that English has words for the talk but not for the stretch of time. Table talk is the conversation and lingering is what you do, but sobremesa is the hour itself, with its own start and its own end. Dutch, oddly enough, has a match in natafelen.
A scene: a Sunday in Madrid, lunch for eight that began at two. By half past four the paella pan has long gone, an uncle is on his third cortado, and the children have been allowed down from the table. The adults are still going over a cousin's wedding, and the sobremesa may well run into dinner.
One false friend to watch: in Portuguese, sobremesa simply means dessert.