Definition of "sarnie"

With their jock-straps pinching, they slouch to attentionWhile queueing for sarnies at the office canteen.

1972, “Thick As A Brick”, Ian Anderson (lyrics), performed by Jethro Tull

In fact no one was playing bingo, 10p or otherwise. Nor had the patrons been enticed by the complimentary shrink-wrapped sarnies and packets of cheese-and-onion on offer in the roped-off ‘Over 18s VIP area’, with its £500-jackpot fruit machines.

2012, Tim Moore, You Are Awful (But I Like You): Travels Around Unloved Britain, Vintage, page 7

Just like Marple, there's a plaque at the London terminus [Paddington] commemorating a fictional character - a polite, friendly little bear from darkest Peru who has a penchant for marmalade sarnies.

2021 September 22, Stephen Roberts, “The writings on the wall...”, in RAIL, number 940, page 74