Loutishness is the quality of being a lout — the rudeness, the roughness, the badly brought-up force in how someone acts. You use it when you want to name the pattern, not one single shove. A newspaper might complain about the loutishness of a few fans, meaning a whole style of behaviour: shouting, shoving, treating a public place as if it were theirs. It is a noun for a fault in manners, and it sounds a little formal and a little scornful, the kind of word a headteacher or a columnist reaches for. Though actually, it is still about ugliness of behaviour, not about being poor or uneducated as such; a rich person can show plenty of loutishness. In everyday talk, people are more likely to say rudeness or bad behaviour. Keep loutishness for when you want that extra stamp of ‘this was coarse, and it mattered’.