scupper

Etymology 1

Uncertain. Perhaps from Middle English scope (“scoop”) or Dutch schop (“shovel”) + -er; or from Dutch scheppen (“to draw off”).

noun

1. (nautical) A drainage hole on the deck of a ship.
2. (architecture) A similar opening in a wall or parapet that allows water to drain from a roof.
   I have said that our roof was decidedly Biblical in style; but to make it a dry one, something of a nautical character was added to its architecture, for on either side were scuppers, and it was slightly arched in the centre[.] 1887, Harriet W. Daly, Digging, Squatting, and Pioneering Life in the Northern Territory of South Australia, page 111

Etymology 2

Of unknown origin; possibly verbized form of Etymology 1, but this is unlikely.

verb

1. (Britain) Thwart or destroy, especially something belonging or pertaining to another.
   Coordinate term: scuttle
   The bad media coverage scuppered his chances of being elected.
   This is the face of American exceptionalism[…] threatening to scupper both the court and, failing that, UN peace-keeping operations in Bosnia and anywhere else the US might have forces deployed on such work. 2002-07-02, Hugo Young, “We can't allow US tantrums to scupper global justice”, in The Guardian
   Anthony Watson’s late interception and Owen Farrell’s 100% kicking contribution also helped scupper the Wallabies, despite the promise of their exciting new centre Jordan Petaia and the roadrunner pace of winger Marika Koroibete. 19 October 2019, Robert Kitson, “England into World Cup semi-finals after bruising victory over Australia”, in The Guardian, London: Guardian News & Media
   Pacers should have all been withdrawn by now, but that has been scuppered by a failure to deliver new trains on time and delays to infrastructure projects. The most high-profile withdrawals were to be Northern's Class 142s and '144s' (the latter by the end of 2018, and the '142s' by the end of last year). May 20 2020, John Crosse, “Soon to be gone... but never forgotten”, in RAIL, page 62