(intransitive) To take suddenly to flight, especially from cover.
A covey of quail flushed from the undergrowth.
1613, William Browne, “The Fourth Song”, in Britannia’s Pastorals. The First Booke, London: […] Iohn Haviland, published 1625, →OCLC, page 83:
But then as little VVrens but nevvly fledge, / […] / His fellovv noting his agilitie, / Thinkes he as vvell may venter as the other, / So fluſhing from one ſpray vnto another, / Gets to the top, and then enbold'ned flies, / Vnto an height paſt ken of humane eyes: […]
1926, Arthur Cleveland Bent, Life Histories of North American Birds: Marsh Birds, page 336:
The birds seem to lie very close and must be nearly stepped on before they will flush.
1972, United States. Congress. Senate. Committee on Appropriations. Subcommittee on Department of Defense, Department of Defense Appropriations for Fiscal Year 1973, page 460:
AWACS is survivable due to its ability to flush on warning, to maneuver at jet speeds, to maintain awareness of the developing air situation and to command weapons as appropriate, including weapons for its own defense.
1712, Humphry Polesworth [pseudonym; John Arbuthnot], “A Copy of Bull and Frog’s Letter to Lord Strutt”, in Law is a Bottomless-Pit.[…], London: […]John Morphew,[…], →OCLC, page 8:
[H]e vvas not fluſh in Ready [i.e., ready money], either to go to Lavv or clear old Debts, neither could he find good Bail: […]
When I would kiss thy hand, / The flush of anger'd shame / O'erflows thy calmer glances, / And o'er black brows drops down / A sudden-curved frown: […]
Any tinge of red colour like that produced on the cheeks by a sudden rush of blood.
the flush on the side of a peach; the flush on the clouds at sunset
1692–1717, Robert South, “Against Long Extemporary Prayers”, in Twelve Sermons Preached upon Several Occasions, volumes (please specify |volume=I to VI), London:
such things as can only feed his pride and flush his ambition
1941, Theodore Roethke, “Prognosis”, in Open House; republished in The Collected Poems of Theodore Roethke, 1975, →ISBN, page 5:
Chill depths of the spirit are flushed to a fever, The nightmare silence is broken. We are not lost.
(intransitive, of a toilet) To be cleansed by being flooded with generous quantities of water.
There must be somebody home: I just heard the toilet flushing.
1667, John Milton, “Book IX”, in Paradise Lost.[…], London: […] [Samuel Simmons], and are to be sold by Peter Parker[…]; [a]nd by Robert Boulter[…]; [a]nd Matthias Walker,[…], →OCLC; republished as Paradise Lost in Ten Books:[…], London: Basil Montagu Pickering[…], 1873, →OCLC:
In her cheek, distemper flushing glowed.
(masonry) To fill in (joints); to point the level; to make them flush.
(mining,intransitive) To operate a placer mine, where the continuous supply of water is insufficient, by holding back the water, and releasing it periodically in a flood.
In sense “turn red with embarrassment”, blush is more common. More finely, in indicating the actual change, blush is usual – “He blushed with embarrassment” – but in indicating state, flushed is also common – “He was flushed with excitement”.