iron [OE] The English word iron probably came from Celtic and was related to Latin aes ‘bronze’ and English ore [OE]. There are many different tools and implements described as irons because they are or were originally made of iron, such as branding irons and fire irons. The expression to have many irons in the fire [M16th], ‘to have a range of options’, comes from the way such tools are made. Blacksmiths have to heat the iron objects in a fire until they reach the critical temperature at which they can be shaped. If they have several items in the forge at the same time they can remove one and hammer it until it has cooled, then return it to the fire to heat up again and work on another. Another phrase from the work of a blacksmith is to strike while the iron is hot [LME], ‘to make use of an opportunity immediately’.

In a speech made in March 1946, Winston Churchill observed that ‘an iron curtain has descended across the Continent [of Europe]’. People often cite this as the origin of the Iron Curtain, the notional barrier separating the former Soviet bloc and the West before the decline of communism after 1989, but the phrase had been used in reference to the Soviet Union in the 1920s, and had the more general meaning of ‘an impenetrable barrier’ as far back as the early 19th century. Its origins actually lie in the theatre. Today’s theatres employ a flame-resistant fire curtain, which in the late 18th century would have been of metal, a genuine iron curtain. See also velvet.