Contd. (site still won't take longer posts, apparently)
And it could be applied to a man, as �brave, gallant, warlike�, which weakened down the years until it was used in the eighteenth century in the phrase �a pretty fellow�, meaning a swell or a fop. But the word also existed in a weakened sense, very much like our modern nice�pleasing or satisfactory in a vague sort of way. In this sense it was applied, in rather a condescending way, to young women as a reduced version of beautiful.
ObvIously, as the word aged the meaning became useful in producing oxymorons such as yours...