What it means
To lob something is to chuck or toss it over, usually without much care for precision. It often means a light throw through the air rather than a proper aimed pass. You hear it in stuff like lob us that or lob it over here. Works for anything from keys to a ball to your bag on the sofa.
Usage examples
"Oi, lob us the remote. He lobs it, it clips the mug and nearly takes my eye out. Calm down, you weapon, I said lob."
"Lob us the keys, I'll go and warm up the car while you lock the back door."
"He just lobbed his bag on the sofa and went straight to the fridge without even saying hello."
"Can you lob me that charger from there? I'm not getting up for it."
"He lobbed his coat over the banister and shouted I'll sort it later, which obviously means never."
Where it comes from
Lob is an old English word that's been around for centuries. It originally pointed to a slow, high, arcing throw or hit, and it's long been at home in sports like tennis and football. The everyday verb keeps that same floaty chuck-it-over feel, just used for normal life stuff.