leath·er / ˈle[voicedth]ər/ • n. 1. a material made from the skin of an animal by tanning or a similar process: [as adj.] a leather jacket. 2. a thing made of leather, in particular: ∎  a piece of leather as a polishing cloth. ∎ short for stirrup leather. ∎  (leathers) leather clothes, esp. those worn by a motorcyclist.• adj. inf. of, relating to, or catering to people who wear leather clothing and accessories as a sign of rough masculinity, esp. homosexuals who practice sadomasochistic sex: leather bar leather queen.• v. [tr.] 1. [usu. as adj.] (leathered) cover with leather: dancers in leathered costumes.2. beat or thrash (someone): he caught me and leathered me black and blue [as n.] (leathering) go, before you get a leathering.

leather hell for leather at breakneck speed (originally with reference to riding on horseback).
leather or prunella something to which one is completely indifferent, the type of something that is of no importance. The term derives from a misinterpretation of Alexander Pope's lines in his Essay on Man, ‘Worth makes the Man, and want of it the Fellow; The rest, is all but Leather or Prunella.’

In the poem, a distinction is being drawn between the trade of a cobbler (leather) and the profession of a clergyman (prunella as the material from which a clerical gown is made). The phrase was however taken to denote something of no value.
there is nothing like leather proverbial saying, late 17th century, referring the toughness and durability of leather. The saying comes from one of Aesop's fables, in which a leatherworker contributed this opinion to a discussion on how to fortify a city.
tough as leather very tough (often figuratively, implying great stamina).

leather Animal hide, treated to make it hard-wearing and resistant to decay. Most leather comes from cattle hide, but many other kinds of skin are used too. The skin is first cured, via a drying process or the application of salt. It is then washed and prepared for tanning, a process that usually consists of treating the skin with a solution of chromium salts or plant extract (tannin). Other processes include dyeing, oiling and the application of various finishes, such as varnish.

leather OE. leðer (only in comps.) = OS. leðar (Du. leer), OHG. ledar (G. leder), ON. leðr :- Gmc. *leþram :- IE. *letrom, whence also OIr. lethar, W. lledr, Breton ler.
Hence leathern OE. leðeren (see -EN3).