1. a gift of public land or resources for the private gain of a limited group

Definition categories: possession, gift

2. an unintentional disclosure

Definition categories: communication, disclosure, revealing, revelation

3. a television or radio program in which contestants compete for awards

Definition categories: communication, broadcast, program, programme

Sentences with giveaway as a noun:

- The T-shirt was a giveaway from the company that sells the software.

- The frosting in his beard was a giveaway that he had been munching the cake.