What is the significance of the title the chaser

The term Chaser is used by drinkers. It means a drink of something bland or sweet to follow-up a straight shot of something like whiskey, gin, rum or tequila. It is called a chaser because it is drunk quickly after the initial strong shot of liquor which has a high alcohol content. John Collier used the word in his title The Chaser because the story talks about the love potion. A man named Alan Austen wants to acquire a love potion from an obscure apothecary. It symbolizes what Alan is doing to Diana that is, he is chasing her love. A chaser is something you drink after drinking something else possibly something unpleasant. The life cleaner offers the inevitable chaser to the love potion Alan buys to make Diana love him. 

a. the scene is structured as a dialogue between two characters in their own informal language.