sash

Etymology 1

From Arabic شَاش (šāš, “muslin cloth”).

noun

1. A piece of cloth designed to be worn around the waist.
2. A decorative length of cloth worn over the shoulder to the opposite hip, often for ceremonial or other formal occasions.
3. (obsolete) Alternative spelling of shash (“the scarf of a turban”)

verb

1. (transitive) To adorn with a sash.
   1796, Edmund Burke, Letters on a Regicide Peace, Letter IV to the Earl Fitzwilliam, in The Works of the Right Honourable Edmund Burke, London: C. and J. Rivington, 1826, Volume 9, p. 46, […] the Costume of the Sans-culotte Constitution of 1793 was absolutely insufferable […] but now they are so powdered and perfumed, and ribanded, and sashed and plumed, that […] there is something in it more grand and noble, something more suitable to an awful Roman Senate, receiving the homage of dependant Tetrarchs.

Etymology 2

From sashes, from French châssis (“frame (of a window or door)”), taken as a plural and -s trimmed off by the late 17th century. See also chassis.

noun

1. The opening part (casement) of a window usually containing the glass panes, hinged to the jamb, or sliding up and down as in a sash window.
   1823, Clement Clarke Moore, “Account of a Visit from St. Nicholas” (“The Night before Christmas”), Away to the window I flew like a flash, Tore open the shutters, and threw up the sash.
   She chiefly recalled the Square under snow; cold mornings, and the coldness of the oil-cloth at the window, and the draught of cold air through the ill-fitting sash (it was put right now)! 1908, Arnold Bennett, The Old Wives’ Tale, Book 4, Chapter 2
2. (software, graphical user interface) A draggable vertical or horizontal bar used to adjust the relative sizes of two adjacent windows.
3. (sawmilling) The rectangular frame in which the saw is strained and by which it is carried up and down with a reciprocating motion; the gate.
4. (chemistry) A window-like part of a fume hood which can be moved up and down in order to create a barrier between chemicals and people.
   Each hood is equipped with two sliding sashes, glazed with polished plate wire-glass; […] 1915 April, W. A. Hamor, “Description of the New Building of the Mellon Institute”, in The Journal of Industrial and Engineering Chemistry, page 334
   […] it [fume hood] also affords an excellent physical barrier on all four sides of a reacting system when the sash is pulled down. 2008, Kenneth L. Williamson, Katherine M. Masters, Macroscale and Microscale Organic Experiments, published 2015, page 35

verb

1. (transitive) To furnish with a sash.
   The old Bow-windows he will have preserv'd, but will not have them sash’d, 1741, Samuel Richardson, Pamela, London, Volume 3, Letter 1, p. 2