An expression of surprise, amazement, pleasure, unexpectedness; or, agreement with sentiments thereof

A thing (ting) that is mad. Derived from Jamaican.

In America, we'd say something is "crazy" if it's unbelievable or surprising (or indeed crazy). In London, the equivalent word is "mad". As in, "He's gone mad!" or "That's absolutely mad, man!"

When someone does something really bad in a funny way

(n.) A phrase used to describe something too awesome or too difficult to understand.

A mad ting is a mad ting

a thing thats good