Green’s Dictionary of Slang

1. a person who buys alcohol legally, and then takes it to a teetotal or ‘dry’ area of the country for consumption.

1911		Truth (Wellington) 12 Aug. 1: The prosecution of ‘keggers’ in and around Invercargill has led to the adoption of the saying, ‘No rest for the beery.’ [DNZE].
1967		F.W. Miller Ink on my Fingers 174 The police kept a tolerant, if suspicious, eye on the ‘keggers’ [DNZE].

2. (US campus) a party featuring a large supply of beer.

1966		Current Sl. I:2 4/1: Kegger, n. A beer party.
1978		W. Hjortsberg Falling Angel 156: ‘No wonder you know about church socials.’ ‘Also square dancing, hotrods, bake sales, Four-H, and keggers’.
1989		D. Waters Heathers [film script] I’m giving Veronica her shot, her first Remington party. You blow it tonight girl, and it’s ‘keggers with kids’ all next year.
1989		J. Doyle College Sl. Dict. 🌐 X kegger [Purdue] Party at which X kegs of beer were consumed.
1999		S. Grafton O is for Outlaw (2000) 389: I’m taking my girlfriend to a kegger out on campus.
2015		‘Chelsea G. Summers’ in Adult 10 Feb. 🌐 I was used to it with the boys I blew under the dusky cover of midnight keggers.