Green’s Dictionary of Slang

1. a euph. for shit n. (3e), i.e. something rubbish or unimpressive.

1997–2000		College Sl. Research Project (Cal. State Poly. Uni., Pomona) 🌐 Shiznet 1. (int.) Expression of disgust.
1997–2001		Online Sl. Dict. 🌐 shiznits adj 1. used instead of shit. Generally considered to be acceptable to a larger audience as it isn’t quite a swear word.
2000		Ebonics Primer at www.dolemite.com 🌐 shiznit Definition: shit: with a snazzy ring to it. Example: Bitch this is some mothafuckin shiznit...you come all da fuckin way ova here, you best gimme some damn sex.
2003		Eble Campus Sl. Nov. 6: shiz – shit.

2. a euph. for shit n. (2c); the ultimate, the best – or the worst.

1996		Eble Campus Sl. Sept. 5: shiznit – something very good or very bad: ‘I’m so tired of this shiznit.’ ‘The play was great. Marcus is the shiznit!’.
1997–2000		College Sl. Research Project (Cal. State Poly. Uni., Pomona) 🌐 Shiz (noun) Cool shit. (Used in reference to music, etc.).
2002		A. Bittel archive Wasted Life 🌐 Thanksgiving is the shiznits. There is nothing better than eating and lushing around watching football.
2002		‘Superlevel’ Endeffect.com posting 8 Oct. 🌐 this game is the mother flunking shiznet!!
2014		C. Eble (ed.) UNC-CH Campus Sl. Spring 2014 13: SHIZNIT — the best. Variant of the shit.