Green’s Dictionary of Slang

1. (Aus.) a 250 ml. bottle of beer [one ‘throws them down’].

2001		Google Groups:alt.tech-support.recovery 23 Jan. 🌐 And one Kiwi or New Guinean brew, what was it- APB Lager? IPC? It had a green label with a picture of a tropical bird on it. We used to call it ‘grenade beer’ because of the way the bottle opened- there was a pull-tab with a finger ring that would pop the cap off.
2003		Aus. Word Map 🌐 The 250ml beer bottles: ‘Pass a hand grenade.’ ‘Throwing down a grenade’ (drinking a 250ml).
2003		Aus. Word Map 🌐 grenade: A small size of stubby (beer container). Also, hand grenade.
2011		S. James in Open Writing: Pure Poetry 22 May 🌐 Each state has its own peculiar terminology for beer measurements and this can be very confusing. A 250ml bottle is referred to as either a ‘grenade’ or a ‘throwdown’, both of which helpfully suggest alternative uses for the glassware once the contents has been guzzled.
2011		Australian Beers.com 🌐 he product is now sold in nearly every imaginable format - cans, stubbies (375ml bottles), throw downs or hand grenades in NSW (250ml bottles).

2. (US campus/teen) an unattractive woman in a female group; someone must talk to her so the rest of the male group can approach her attractive friends [the image of a soldier throwing himself on a grenade to save his buddies’ lives].

2003		Urban Dict 29 Aug. 🌐 Grenade The solitary ugly girl always found with a group of hotties. If the grenade doesn’t get any action, then neither does anyone else ‘Come on man, take one for the team and jump the grenade’.
2012		M. Lacher On the Bro’d 22: ‘I was on the porch alone with a total grenade’.