Staple

OED (1915) lists four separate nouns, one adjective and two verbs written staple; the last three are all related to one of the nouns. Some of the meanings have little interest except to historians.

• The first (OED staple n.¹) comes from the Old English stapol, which had a general sense of 'support'. It could be used for 'pillar', 'post' or 'leg [of a table or chair, etc]'; and in general Old Germanic 'stocks' on which ships were built; 'a platform'; 'the stem of a plant'; 'a stake [in a fence or building, etc]'; 'a block [for executions]'; 'foundation [of a building]'. It probably shares the root of step. The current meanings of OED's staple n.¹ include:
  • a short metal bar formed like the letter 'u', having the two ends sharpened so that it may be driven into wood or other material, used as a fastener. (It is this noun that gives rise to OED's v¹ "To secure with or as with a staple".)
    • The older forms of staple were used to fasten materials together. With doors and other movable items, they are often used with a hasp - a hinged device, another 'u'-shaped piece of wire or a metal plate with a slot - which passes over a staple and may be padlocked or simply pinned to it. Small staples are commonly seen clamping electrical cable to wooden bases: the 'u' of the staple holds the cable without cutting into it. Staples which stand proud of the material in which they are driven, leaving a gap, can be used like rings, for tethering horses, mooring boats, or in general fastening cords. In the construction industry, staples may be fixed using a staple gun, which may be manually, electrically or pneumatically powered.
    • The staples perhaps most familiar to modern students are those to fasten sheets of paper together. These were developed in the last quarter of the nineteenth century. They are fixed with a stapler.
    • More technical and limited meanings include 'the metal mount for a reed in an oboe'; 'the ring in the nose of a pig'; and 'a pillar of coal left as a support in a coal-mine'.
• OED's staple n.², whose original meaning - which has interest only to those studying history, but has importance in the study of medieval economics - comes from the Old French estaple 'a market[-place]' (the origin of the name of the French town Étaples). This appears to arise from regis stapulus in the Frankish laws of around 500 CE, which meant 'the place where the king or his representative administered judgement'. This may share the root of n¹ stapol in the sense of 'raised platform [from which the government issued orders and kept control]' (OED, 1915; but OED has glossed the two nouns separately). This noun gives rise to OED's v², which has two technical - and obsolete - meanings.
  • In European history, a Staple (note the upper case S-) was a town appointed by the crown to have privileges in exporting or trade generally. In England, the most important (The Staple) from about 1390 to 1558 was at Calais, which had a monopoly on the export of wool and leather. There were many other local staples, for example those established by Edward III at Carmarthen, Dublin, Waterford, Cork, and Drogheda; and there were Staples belonging to other nations, such as the 'Scotch [sic] Staple' and the Hanseatic Staple; and many towns in the low countries claimed a droit d'estaple which required all goods being carried on their waterways to be exhibited for sale when they passed through or pay a toll.
    • The meaning of 'a privileged market' had certain related terms. A merchant of the Staple was a trader with privileges, in due course being a member of The Company of Merchants of the Staple, one of the oldest mercantile corporations in England. The Staple was regularized under the Statute of the Staple in 1353 under Edward III. As time passed, the meaning of staple expanded:
    • 'a trading centre for a particular product or good', as Malacca was said to be "the staple of the Traffique..of the East Ocean" (Botero, G. [translator not identified] (1630) Relations of the most famous kingdomes and common-wealths, cit. OED 1915. This became more centrally 'an important market [town or port]', sometimes a settlement or colony of foreign merchants settled abroad, as the Steelyard in London was the base of the Hanseatic merchants.
    • A staple could also be a store or stockpile of the materials dealt with inside the place, or an arsenal of warlike material, etc.
    • Naturally enough this expanded to mean 'the [or a] principal product of the town or area', as the staple of Birmingham for many years was small-scale metal-working. In agricultural areas, it was the principal crop of the area, as sugar was in the Caribbean islands and beef-ranching was the staple of the western states of the USA.
    • This transferred to 'the principal food eaten in an area'; 'the basic subsistence of [a group of] people', as oats was said to be the staple of the Scots, and potatoes of the Irish - helping to magnify the effects of the Irish Potato Famine of 1845-1852.
    • Figuratively, the staple can be 'the chief part [of anything]', 'the central topic [of conversation, etc]', 'the main topic of discourse' (Sydney Smith said that the weather "forms the great staple of polite English conversation"); and it can be said that the staple of many friendships is conversation - and that the staple of many conversations is gossip.

These meanings of staple are the source of the adjective staple, which is simply the epithetical use of OED's staple n.²: nowadays, it is more common to see the phrase staple foods and staple goods than the bare noun staples.

• OED's staple n.³ means 'a quality of length, fineness or straightness, etc, in wool [and later other textiles'; 'a lock of wool'; 'the fibre of which thread is spun'. Although OED gives its etymology as 'obscure', this meaning is to do with wool - and its root may well be OED's staple n.², as one of the functions of a Merchant of the [wool] Staple was to sort wool and assess its quality.

OED's staple n.⁴ is also 'Of obscure origin'. It is a northern term used in coal mining, and is the opposite of the use of OED's staple n.¹ in mining: where that is a mass left in support, OED's staple n.⁴ is a hollow - a shaft sunk underground between different seams. This staple is pronounced to rhyme with 'chapel' - IPA: /ˈsta (or æ)p ^əl/.

• Of the two staplers recorded,
  • by far the commoner in modern English is OED's stapler n.² (first recorded in 1951), "A device for fastening together papers, etc., with a staple or staples."
  • The older, and hardly current outside historical writing, is OED's stapler n.¹, "A merchant of the Staple [n.²]", and some related meanings.

Don't confuse staple with stable, by careless keyboarding or pronunciation.