
As you might expect, the use of '-Gate' stems from metonymy. The 1972 political scandal that led to Richard Nixon's resignation became popularly known as 'Watergate,' named after the hotel and office complex where burglars connected to the administration were caught attempting to break into the Democratic National Committee headquarters.
But how did the NFL's 'Deflategate' come into being more than 40 years later? When did this specific suffix become so commonplace?
It didn't take long, it seems. The news of the original Watergate break-in and subsequent cover-up broke in June 1972. In the year following, the press began using terms like 'Watergatery' or calling dishonest politicians 'Watergaters,' showing how quickly the scandal had embedded itself into language. Less than a year after the event, the '-gate' suffix was first used in a satirical piece in the August 1973 issue of National Lampoon magazine, which coined the term 'Volgagate' in reference to a fake Russian scandal, directly drawing a parallel to Nixon's Watergate.
William Safire, a former speechwriter for Nixon, is widely recognized for popularizing the '-gate' suffix during his tenure as a New York Times columnist. In a 1996 issue of New York magazine, Noam Cohen critiques Safire, compiling a 'condensed dictionary' of '-gates' coined by the columnist and accusing him of attempting to 'rehabilitate Nixon by tarnishing his successors with the same rhetorical technique—diminishing guilt through association.'
(Safire later acknowledged that this critique may not have been entirely off the mark in Eric Alterman's Sound and the Fury: The Making of the Punditocracy. Alterman writes: 'Safire now admits that, psychologically, he may have been attempting to downplay the significance of the crimes committed by his former boss with this triviality.')
By this time, however, Safire and others no longer needed justification to use the '-gate' suffix. In 1993, Merriam-Webster added the scandal-based definition to their dictionary.
