Airs and graces

To put on airs and graces is to behave in a false, affected manner, making pretensions to high social standing, sometimes shortened to ‘put on airs’. An ‘air’ is a manner or appearance and the word has been used in this way since the late 1500s, while a ‘grace’ is an attractive or pleasing feature and dates in this sense from The Middle Ages. Putting the two together, in the expression as we now know it, dates from the late 18th century, as does the shortened version ‘put on airs’.