calibre [M16th] This word, now meaning ‘the quality of someone’s character or ability’ and ‘internal diameter or bore of a gun barrel’, travelled around the Mediterranean and Middle East before arriving in English during the 16th century. It may have started in Greece, from where the word kalapous, ‘shoemaker’s last’, migrated east and became Arabic qālib, ‘mould for casting metal’. The jump to Italy or Spain and then France produced the spelling calibre, and from there it came to England, where it first meant ‘social standing or importance’. The sense changes seem to have been from the mould to metal to something for casting bullets, then since the calibre of a gun determines its effectiveness this was interpreted as indicating personal qualities. Calliper [L16th], which would have been used for something to measure the diameter of a bullet, is an alteration of calibre.