a second drink, usualy a shot (ie spirit without mixer) to be consumed with, or after (hence chaser) another drink, probably a pint of beer, or a long mixed dring.
contrast with a mixer, which is a (usualy non alcoholic) drink which is added to spirits to make them more flavourful, or less potent.
yeah thanks ill have another beer, and get some tequila chasers, its half ten and i can still stand up.
When you break the sticks off of bottle rockets, creating a condition where lighting them causes them to fly in all directions, causing widespread panic in a somewhat confined space.